@@abhishekmaurya519 I am thinking the same. Like this is undoubtedly quality content but all I'm worried about is weather this content for CAT is still efficient or not? What do you think about these sets on cubes? Do cube questions still come in cat?
@@sattwickdas2686 bro listen we can't say this is right or this is wrong or this can come or this won't, until and unless u r going through each and every videos and concepts so in the end of the day, u r still be in search of a perfect mentor but u won't get one coz no one will reach to your level of expectation
For question no 4. 26:20 We can also calculate like this- 1+(27+5)+(53+10)+(79+15)+(105+20)=315 Using front face diagonal concept. 1,27,53,79,105 is taken because if we make a front face diagonal from 1 to 105 all these numbers will come. Just reverse of 2nd question. For every layer multiply 5 with the below layer number because it's a 5*5*5 cube. Like for number 27 its 1 layer above the bottom layer therefore 27+1*5=32 For 53 ( 53 + 2*5=63) and so on. Hope it helps. I personally find this method a bit faster and Sir, you are great.
Prateek Sinha I have a question y did sir take new series to number the bottom later not continuing the same series on vertical phase ? Can u plz ans it
Also while adding the numbers we can see that all 4 questions form an AP, so we can use the formula for sum of AP having odd terms = (middle term * no of terms) : Therefore : 1. 10+35+60+85+110 (AP with a= 10 and diff=25) Ans: 60*5=300 2. 53*5=265 3.28*5=140 4. 63*5 =315
Thank you for all the series of CAT, Best Teacher. THANK YOU AGAIN. I haven't seen any other series like this...keep going sir. .Rodha doing the great work. .
The first question asks the *sum of numbers * on the smaller cubes FORMING A VERTICAL EDGE OF LARGER CUBE that is xyz. But the column 10,35,60,85,110 doesn’t form an edge. But the 25,50,75,100,125 forms an edge and also is behind the right edge of front face of the larger cube but of course *not immediate* please explain.
In the first question I have a doubt that numbers 10,35,60,85,110 are not forming a edge on the larger cube. Shouldn't the numbers be 25,50,75,100,125?
you are a blessing sir. I am taking classes from a very reupdated institute of the country but the understanding comes from you is different. whenever i get tensed about my CAT syllabus I am like Rodha sir hai naaaa.....Thankyou sir God bless you.
Thank You .... You have the most lucid , non - rushing teaching methodology i have ever come across . Thank you and God bless you . Your effort has improved my Thinking ability .
@@raviprakash6021 Yes Sir I have seen your lectures of geometry.. U really make things crystal clear.. Superb teaching sir.. I am really very thankful to you for making videos with awesome explaination.
Sir, you are doing a great job, from anywhere you haven't chance for preparing CAT without any cost, but here it is and it's a massive video for preparing CAT without money, you are a gem sir❤️❤️
The way you teach is great level sir. It is the first time in my youtube history that I pause a video and like it and then continue. Great sir. thank you. 🙏🙏
Yesterday attended a mock and a question was asked on Cubes at that moment i am unable to solve that but after watching this video That set easily soved.Thanks a lot sir for developing this visualization and explaining this concept was fabulous and outstanding.Hats off you Sir
This is brilliance, both of concept and teaching skills personified, not everyone can explain such visualisations, even after understanding it , kudos to you sir for explaining such a complicated topic so beautifully , thank u for bringing such quality education within reach for aspirants like me🙏
Explanation was simply amazing. Understood it completely. But the wording of the case study is confusing. Hoping to get more practice and improve my understanding. Thank you so much Sir
Sir you are the best teacher that I have ever seen who is putting in a lot of effort to make us understand the concepts and providing such incredible knowledge for CAT preparation, hats off to you Ravi prakash sir ❤️❤️
Easy way of calculating the last question is noticing the pattern (1 + 30*0)+(2 + 30*1)+... regroup them as (1+2+3+4+5)+30*(0+1+2+3+4) and use sum of natural numbers giving you 15 + 30*10 = 315
This series is seriously amazing. Thank you sir for making the effort to make us visualize . It ir really difficult to make someone visualize this type of diagram with pen and paper. And you have done it on computer screen that is more difficult. Thank you sir🙏
sir, no. on smaller sqs forming the vertical edge of the larger cube which is immediately behind the right vertical edge of front face would be the sqs 25,50,75,100,125 as the sqs 10,35,60,85,110 are not forming any vertical edge of the larger cube , please explain,. sir i am totally depending on videos to study please help me out
the way you teach explaining the logic behind each and every thing is incredible, things which I used to cram because of your teaching I am able to understand the concept behind each and everything. Thank you sir! your videos and teaching is indeed a blessing. :)
Did it all by myself sir by making drawing, only was a small addition mistake, rest answers were correct, but also learned the fast way by seeing your solution. Thank you so much sir!! 😇
well the last ques can be done in much easier way. the first cube is at position 1 and last one is at 125. ther are total 5 cubes in the diagonal. main observation: he common diff between consecutive diagonal cubes will be same hence there are 5 cube no starting with 1 and ending with 125 in ap with 5 terms. so total sum = 5*(1 + 125)/2
29:43, I derived answer through an other way.Sir, is it right way to solve if we are getting right answer. Body diagonal is being formed by layerth cube, I mean first in first layer 2nd in second layer, 3rd in third layer , 4th in Fourth layer and 5th in 5th layer. Here, 1 is first small cube for first layer and 32 for 2nd similarly for other. and gap between these consecutive small cubes is of 31 and by the help of arithmetic series formula: =n/2(first element + Last formula) =5/2(1+125) =5 x 63=315
I always feel that Animation images don't develop our thinking level. It's WOW just for that moment but after that we again can't think in another problem. That's how I teach my full course of 400 LRDI SETS. :)
Thank you for the wonderful initiative of teaching individual topics sir. I study in career launcher and even they dont explain different topics like this.
I'm so happy! Now because you explained first set so incredibly I was easily able to visualise the 2nd set accurately! Amazing job 👏 I stopped the video and solve 2nd, 3rd, & 4th question before you and all of them were right because you explained the 1st question so well!
sir last question is easy if it is solved with the help of a series like 1+125=126(means 1st and 5th term addition is 126),therefore 2nd and 4th term addition is also 126 and for 3rd term it will be half and all of them will give 315
In the first question the sum of numbers of smaller cubes which form vertical edge of bigger cube has to be calculated. The second row which sir has calculated is not the edge of the bigger cube. I think that the last row with small cubes numbered 25, 50, 75, 100 and 125. It should amount to 375. I do not know if this is the right analogy, correct me if I am wrong.
In question 1, we need vertical edge of large cube right? this 10-35-60-85-110 is not edge of large cube sir. There is specifically mentioned the vertical edge of larger cube. vertical edge of larger cube is: 25-50-75-100-125. Pls clear doubts sir
i suber trick i woud like to share is that in last question 4 , if you have studies quant AP , you can just simply do sum of first + last term /2 . (125+1)/2 = 63 * no of terms (to get the sum) i.e. 63*5 = 315 🤯
For question 4th for every n=1 to 5, we can see that it follows the form of n + (n-1)5 +(n-1)25 = n + (n-1)30 ….calculating this way also we can get the same ans.
Definitely Great Work Sir!!! But one suggestion in the videos having Questions please in the description add answers to the questions So we can directly verify them with ours.
Sir in the 1st question, it's not the edge u have calculated it for, shouldn't it be the the sum of 25+50+....125 since that is an edge, one of the 12 edges of the larger cube ?
I also think it should be the sum of 25+50+...125. As It told to find the sum of smaller cube forming verticle edge, that is right behind the right verticle edge of front side. Can anyone clear this out please?
@@sahilmortuza3543 Go from reverse of question. immidiately behind the right vertical edge of front face of larger cube. front face is only the one face where 1-125 numbers are written. the right most front edge is the numbers from 5,30,55,80,105.
All of them can be solved using AP as well, as we know that the difference is equal each time. Also, we can see a pattern in all questions due to the symmetry of the cube. Now, in question 4, we can go like this:- the first term is 1, second can be figured out by looking at the diagram, so 32. We can see there is a gap of 31, just form an AP using this. Next would be 63. Now, we don't even need to calculate after this, as in an AP, the middle term ( avg. )* n is the sum of AP. An even better way would be:- As we know the first and last term and there is symmetry as well, so, (1+125)/2 = 63, and 63*5 = 315 which is our answer. ALSO, I'm pretty sure that in question number 1, "The vertical edge" that was mentioned was = 25, 50, 75, 100, 125, as it is clearly mentioned that it is an EDGE and the layer of 10,35,60,85,110 didn't form an edge. Would highly appreciate it if Ravi sir, or someone else would confirm this.
The 1st question should have been "What is the sum of the numbers on the smaller cubes on the column that is immediately behind the right vertical edge of the front face of the larger cude?"
Can be put in this way : Difference between numbers of adjacent cubes in- 1. x axis= 1 2. y axis= 25 3. z axis= 5 To get next number of an edge : add common difference of that axis to previous number To get next number of a face diagonal : add cd's of both axes in which the face lies. To get next number of a body diagonal : add cd's of all 3 axes.
sir in question 1 that states smaller cubes forming vertical edge, immediately behind the right vertical edge which i understood that we have to find out sum of the group of small cubes which makes vertical edge immediately behind the right edge of large cube so it will be 25-50-75-100-125 how am I wrong please guide me.
Hello sir, in the 1st question it's mentioned that the cubes forming a vertical edge of larger cube. But you told that the cubes numbered from 10 to 110 is the answer but it's not forming a vertical edge of the cube. So can the answer be the cubes numbered from 25 to 125 bcz it's edge of the cube which is behind the right edge of the front face. Please clear my doubt.
In question no. 1 sir question asks us the small cubes that form the EDGE of the circle. Shouldn't they be 25, 50, 75, 100, 125? Because the cubes that you have taken 10, 35, 60, 85, 110 do not form the EDGE OF THE LARGER CUBE. Please please explain
Sir we can try one more way to solve the question no 4 which is internal diagonal for that we have data as cube no 1 and last that is 125 we need to add both and divide by two we will get 63 the centre one again we add 1 and 63 divide by 2 we will get 32 and again we will add 63 and 125 and divide by 2 we will get 84 add all those we have our answer that is 315. Thank you
In the first question. They have asked for the sum of the numbers of cubes which form the vertical edge of the larger cube behind the right edge of the front face of the larger cube. In the video sir has taken the cubes just behind the right vertical edge of the front face of the larger cube. Are these cubes form the vertical edge of the larger cube? I think the answer is no. Does anyone have any ideas regarding this. Thanks in advance.
Hi the question specifies that the smaller cubes form the vertical edge of the larger cube and we have to find the sum of cubes bebind the same. The behind cubes are just immediate.
it is lil difficult for a teacher to make us visualise that diagram and explaining on screen. no doubt sir has done it incredibly ..
Exactly
hey omi, where you at now...did you get into some good college
@@abhishekmaurya519 I am thinking the same. Like this is undoubtedly quality content but all I'm worried about is weather this content for CAT is still efficient or not? What do you think about these sets on cubes? Do cube questions still come in cat?
@@sattwickdas2686 bro listen we can't say this is right or this is wrong or this can come or this won't, until and unless u r going through each and every videos and concepts so in the end of the day, u r still be in search of a perfect mentor but u won't get one coz no one will reach to your level of expectation
Cat exam nikali kya appki
Hi all.. ERRATA .. at 26:50 , it is (25+4*25) not 25+(4*100)
Thank u sir for the correction
Ravi sir be like, 'how was i so much confident at the time of teaching and saying 25+(4*100) is 125. hahaha
Although he wrote it wrong but he is calling it 125 . Sometimes it happens to us too right! Avoid that. We all know he is excellent at his work.
Sir is there any whatsapp group . Can you please share the link 🙏.....thankyou so much sir. I would always be grateful for what you are doing ❤️
Was banging my head for 10 mins wondering where did that 100 come from n its an error :")
For question no 4. 26:20
We can also calculate like this- 1+(27+5)+(53+10)+(79+15)+(105+20)=315
Using front face diagonal concept.
1,27,53,79,105 is taken because if we make a front face diagonal from 1 to 105 all these numbers will come.
Just reverse of 2nd question.
For every layer multiply 5 with the below layer number because it's a 5*5*5 cube.
Like for number 27 its 1 layer above the bottom layer therefore 27+1*5=32
For 53 ( 53 + 2*5=63) and so on.
Hope it helps. I personally find this method a bit faster and
Sir, you are great.
Hey puneet you got any good collage?
Me too find it myself alhamdulillah
But efforts of rodha sir is always best
@@ayushop5312 hey ayush !
are preparing for cat ?
I did that exact thing too and I find it faster and more convenient.
In this 2D world education ,,this sir is in next level of 3D 🔥🎉 thank you so much from all aspirants 🎉🎉 for this quality content 🙏
First question is tricky. One needs to have a good hold on English primarily to understand the questions 🥺
I had solved this question earlier. And it had taken me almost 15 minutes. After seeing this video, I solved it in mere 5 minutes.
Prateek Sinha I have a question y did sir take new series to number the bottom later not continuing the same series on vertical phase ? Can u plz ans it
Same question even for me 😢@@behindthescene4406
Also while adding the numbers we can see that all 4 questions form an AP, so we can use the formula for sum of AP having odd terms = (middle term * no of terms) :
Therefore : 1. 10+35+60+85+110 (AP with a= 10 and diff=25) Ans: 60*5=300
2. 53*5=265
3.28*5=140
4. 63*5 =315
ua-cam.com/video/jCJs365q9Ok/v-deo.html
Smart 👍
DAM IN WHICH IIM YOU WERE
Thank you for all the series of CAT, Best Teacher. THANK YOU AGAIN. I haven't seen any other series like this...keep going sir. .Rodha doing the great work.
.
The first question asks the *sum of numbers * on the smaller cubes FORMING A VERTICAL EDGE OF LARGER CUBE that is xyz. But the column 10,35,60,85,110 doesn’t form an edge. But the 25,50,75,100,125 forms an edge and also is behind the right edge of front face of the larger cube but of course *not immediate* please explain.
Also there's another possibility..... taking the left edge(behind 1)
exactly, I'm aslo confused in it Did you got the answer?
@@regalchaudhary1 I also got struck with this one, did you get the answer?
i have the same question why did he pick 10 as the base of an edge 10 is not a part any edges
@@manishsrcc I got stuck here too, did you get the correct answer?
Seeing and visualizing is actually fun and makes me more involved. - A beginner :) ty sir !!!
my 3rd day
are you also preparing for cat
In 1st Q it is asked about vertical edge....which is immediately behind.....not cubes immediately behind.
Ans:375
Thank you sir for putting your 100% on youtube just to make us understand . Respect ++++🙏🏻🙏🏻👏🏻👏🏻
I am completely dependent on you for CAT 2021.
Thank You Soo much for this excellent content for free.. You really are great ! ❤️❤️❤️
Me too😅😅
How much percentile did you get?
How much did u got , whether this channel get u into good clg?
What suggestions do u give to the freshers who are preparing from this channel alone...
What percentile did u get?
Reply ur result
In the first question I have a doubt that numbers 10,35,60,85,110 are not forming a edge on the larger cube. Shouldn't the numbers be 25,50,75,100,125?
exactly
question states that the edge of the larger cube
you are a blessing sir. I am taking classes from a very reupdated institute of the country but the understanding comes from you is different. whenever i get tensed about my CAT syllabus I am like Rodha sir hai naaaa.....Thankyou sir God bless you.
So nice of you. ThankYou. My name is RAVI PRAKASH by the way. :)
I think only you can explain in the best possible way via online screen. Blessed to learn from you Sir!!
Thank You .... You have the most lucid , non - rushing teaching methodology i have ever come across . Thank you and God bless you . Your effort has improved my Thinking ability .
For that's what I teach .. to improve thinking ability and IQ level
@@raviprakash6021 Yes Sir I have seen your lectures of geometry.. U really make things crystal clear.. Superb teaching sir.. I am really very thankful to you for making videos with awesome explaination.
@@raviprakash6021 Can u pls upload videos for D.I as well!!!!
Sir, you are doing a great job, from anywhere you haven't chance for preparing CAT without any cost, but here it is and it's a massive video for preparing CAT without money, you are a gem sir❤️❤️
Wonderful explanation. Initially got confused and thought of skipping it but now after 1hour of observation, understood and solved it. Thank you Sir
Thank you for your explanation sir, in question 1 it is asking vertical edge behind front face vertical edge
i always found this topic difficult to understand but you have made this easier thank you so much sir. your teaching style is just "wow"
The way you teach is great level sir. It is the first time in my youtube history that I pause a video and like it and then continue. Great sir. thank you. 🙏🙏
Yesterday attended a mock and a question was asked on Cubes at that moment i am unable to solve that but after watching this video That set easily soved.Thanks a lot sir for developing this visualization and explaining this concept was fabulous and outstanding.Hats off you Sir
This is brilliance, both of concept and teaching skills personified, not everyone can explain such visualisations, even after understanding it , kudos to you sir for explaining such a complicated topic so beautifully , thank u for bringing such quality education within reach for aspirants like me🙏
There is small correction that in (que.4) you by mistakely written 25+ 4*100 but it will be 25+ 4*25.
After watching your video there is self confidence boost up itself. thank you making our work easier. Thank🙏💕🙏💕
According to me -This is so difficult topic but you explained so easily thank you so much sir 👍
Explanation was simply amazing. Understood it completely. But the wording of the case study is confusing. Hoping to get more practice and improve my understanding. Thank you so much Sir
Sir you are the best teacher that I have ever seen who is putting in a lot of effort to make us understand the concepts and providing such incredible knowledge for CAT preparation, hats off to you Ravi prakash sir ❤️❤️
Mashallah You are really one of the greatest teacher may God give you All the highest respect and position ❤❤❤❤
Did this question without even pen and its my 3rd question of DLRI...
All hail to RAVI SIR
Got all the questions right in the first attempt, loved it and it boosted my confidence as well. Thank you sir!
at 28:21, it should be 25+4*25 =125 , I think, please correct me if I'm wrong!
Easy way of calculating the last question is noticing the pattern (1 + 30*0)+(2 + 30*1)+...
regroup them as (1+2+3+4+5)+30*(0+1+2+3+4) and use sum of natural numbers giving you 15 + 30*10 = 315
ua-cam.com/video/jCJs365q9Ok/v-deo.html
You made us visualise this in the Best Way Possible considering the resources at hand
This series is seriously amazing. Thank you sir for making the effort to make us visualize . It ir really difficult to make someone visualize this type of diagram with pen and paper. And you have done it on computer screen that is more difficult. Thank you sir🙏
Such a good job sir ❤️ you are the example of super 30s anand sir
sir, no. on smaller sqs forming the vertical edge of the larger cube which is immediately behind the right vertical edge of front face would be the sqs 25,50,75,100,125 as the sqs 10,35,60,85,110 are not forming any vertical edge of the larger cube , please explain,. sir i am totally depending on videos to study please help me out
the way you teach explaining the logic behind each and every thing is incredible, things which I used to cram because of your teaching I am able to understand the concept behind each and everything. Thank you sir! your videos and teaching is indeed a blessing. :)
Did it all by myself sir by making drawing, only was a small addition mistake, rest answers were correct, but also learned the fast way by seeing your solution. Thank you so much sir!! 😇
at last it will be +(25 + 4 x 25) instead of +( 25+ 4 x 100)
Correct !! We can also use this concept in last = 1 + (27+5) + (53+10) + (79+15) + (105+20)
Sir I call Rodha and you thank , you teach very well sir, your method is too good, thank you sir for doing so much for us.🙏🙏🙏❣️❣️
well the last ques can be done in much easier way. the first cube is at position 1 and last one is at 125. ther are total 5 cubes in the diagonal. main observation: he common diff between consecutive diagonal cubes will be same hence there are 5 cube no starting with 1 and ending with 125 in ap with 5 terms. so total sum = 5*(1 + 125)/2
Sir I am unable to understand the numbering of the cubes. Please explain it
Last question (or any que) : They are in AP, so we can just make it:- (first term (i.e. 1) + last term (i.e. 125) )*no. of terms (i.e. 5) / 2
I was thinking the same. Wonder why he didn't tell us that trick
the best cat mentor i could have ever find in both lrdi and quant
29:43, I derived answer through an other way.Sir, is it right way to solve if we are getting right answer. Body diagonal is being formed by layerth cube, I mean first in first layer 2nd in second layer, 3rd in third layer , 4th in Fourth layer and 5th in 5th layer. Here, 1 is first small cube for first layer and 32 for 2nd similarly for other. and gap between these consecutive small cubes is of 31 and by the help of arithmetic series formula:
=n/2(first element + Last formula)
=5/2(1+125)
=5 x 63=315
this works too.
Great efforts to make everyone understand diagram with visualization and explaining on screen. Excellent sir thank you!
Without animation images you did it very nicely . Good work sir.🙏
I always feel that Animation images don't develop our thinking level. It's WOW just for that moment but after that we again can't think in another problem. That's how I teach my full course of 400 LRDI SETS. :)
@@Rodha nice sir 👏.
Incredible sir!!! Thankyou for quality stuff!!! You are GURU in true sense!!!
Thank you for the wonderful initiative of teaching individual topics sir. I study in career launcher and even they dont explain different topics like this.
Thank sir u r one of the best teacher
Now I have mastered my cubes just because of u😀
ua-cam.com/video/jCJs365q9Ok/v-deo.html
This explanation was made so easy to understand, literally hats off sir. Thank you for the knowledge.
this question is so tricky, anyways ravi sir explained it so nicely..Dimaag khull gya sir.
I'm so happy! Now because you explained first set so incredibly I was easily able to visualise the 2nd set accurately! Amazing job 👏
I stopped the video and solve 2nd, 3rd, & 4th question before you and all of them were right because you explained the 1st question so well!
Sir you are so good at teaching . 🙌🙌🙌🙌
sir last question is easy if it is solved with the help of a series like 1+125=126(means 1st and 5th term addition is 126),therefore 2nd and 4th term addition is also 126 and for 3rd term it will be half and all of them will give 315
best teacher on youtube for lrdi... sir please upload more videos
In the first question the sum of numbers of smaller cubes which form vertical edge of bigger cube has to be calculated. The second row which sir has calculated is not the edge of the bigger cube. I think that the last row with small cubes numbered 25, 50, 75, 100 and 125. It should amount to 375. I do not know if this is the right analogy, correct me if I am wrong.
I think question is asking the sum of vertical edge so 375 should be the right answer
Exactly.
In question 1, we need vertical edge of large cube right? this 10-35-60-85-110 is not edge of large cube sir. There is specifically mentioned the vertical edge of larger cube.
vertical edge of larger cube is: 25-50-75-100-125. Pls clear doubts sir
You r right
Great video..I am preparing for 2021 n it's helpful
i suber trick i woud like to share is that in last question 4 , if you have studies quant AP , you can just simply do sum of first + last term /2 . (125+1)/2 = 63 * no of terms (to get the sum) i.e. 63*5 = 315 🤯
For question 4th for every n=1 to 5, we can see that it follows the form of n + (n-1)5 +(n-1)25 = n + (n-1)30 ….calculating this way also we can get the same ans.
In last question we also take body diagonal difference that is 31
So, 1+ 32+ (32+31)+(32+31+31)+(32+31 +31 +31) = 125
Isn't the first qstn asking about the vertical edge(cubes) behind the right vertical edge??
So the answer can be 25+50+75+100+125??
The questions reads immediately behind. Check once
I was having a very hard time with cubes. You made it so easy :)
thank you sir, for a NON engg. student like me, understanding and imagining this concepts was very difficult , but this videos have helped me a lot
Sir your teaching skills are just awsm🙏
Definitely Great Work Sir!!! But one suggestion in the videos having Questions please in the description add answers to the questions So we can directly verify them with ours.
Thank you sir, needed a little revision on cubes, watched these 4 videos and it helped a lot!
Sir in the 1st question, it's not the edge u have calculated it for, shouldn't it be the the sum of 25+50+....125 since that is an edge, one of the 12 edges of the larger cube ?
I also think it should be the sum of 25+50+...125. As It told to find the sum of smaller cube forming verticle edge, that is right behind the right verticle edge of front side. Can anyone clear this out please?
@@sahilmortuza3543 Go from reverse of question.
immidiately behind the right vertical edge of front face of larger cube.
front face is only the one face where 1-125 numbers are written. the right most front edge is the numbers from 5,30,55,80,105.
yes exactly 10+35+. .+110 is not forming vertical edge.
25+50+. .+125 is . also as it is the only vertical edge behind the front face edge.
Exactly, the answer should be 25+50+...125=375
So in general you can only number above layer after completing the lower layer of the cube
In the last question, there's an AP and we can use the method by using first and last term i.e. average× no. Of terms= sum
All of them can be solved using AP as well, as we know that the difference is equal each time. Also, we can see a pattern in all questions due to the symmetry of the cube.
Now, in question 4, we can go like this:- the first term is 1, second can be figured out by looking at the diagram, so 32. We can see there is a gap of 31, just form an AP using this. Next would be 63. Now, we don't even need to calculate after this, as in an AP, the middle term ( avg. )* n is the sum of AP.
An even better way would be:- As we know the first and last term and there is symmetry as well, so, (1+125)/2 = 63, and 63*5 = 315 which is our answer.
ALSO, I'm pretty sure that in question number 1, "The vertical edge" that was mentioned was = 25, 50, 75, 100, 125, as it is clearly mentioned that it is an EDGE and the layer of 10,35,60,85,110 didn't form an edge.
Would highly appreciate it if Ravi sir, or someone else would confirm this.
The 1st question should have been "What is the sum of the numbers on the smaller cubes on the column that is immediately behind the right vertical edge of the front face of the larger cude?"
Sir is saying that 1-25 is the bottom layer, then how come he has written 10 in that right faced cube
Anyone can clear it please?
sir incredible......noone else can make understanding like this..
All sessions are fantastic and the teaching style is very very good 👍
Can be put in this way :
Difference between numbers of adjacent cubes in-
1. x axis= 1
2. y axis= 25
3. z axis= 5
To get next number of an edge : add common difference of that axis to previous number
To get next number of a face diagonal : add cd's of both axes in which the face lies.
To get next number of a body diagonal : add cd's of all 3 axes.
Ravi prakash sir on his best❤❤❤❤
What a fantastic question !!
Brilliant question ,will practice this more times!
sir in question 1 that states smaller cubes forming vertical edge, immediately behind the right vertical edge which i understood that we have to find out sum of the group of small cubes which makes vertical edge immediately behind the right edge of large cube so it will be 25-50-75-100-125 how am I wrong please guide me.
Hello sir, in the 1st question it's mentioned that the cubes forming a vertical edge of larger cube. But you told that the cubes numbered from 10 to 110 is the answer but it's not forming a vertical edge of the cube. So can the answer be the cubes numbered from 25 to 125 bcz it's edge of the cube which is behind the right edge of the front face.
Please clear my doubt.
Thankuu so much sir...you have explained very nicely... Nobody can explain in this way..
In question no. 1 sir question asks us the small cubes that form the EDGE of the circle. Shouldn't they be 25, 50, 75, 100, 125? Because the cubes that you have taken 10, 35, 60, 85, 110 do not form the EDGE OF THE LARGER CUBE. Please please explain
it will be 25+4*25
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good job sir , thank you for your effort you are putting in making these videos . helping the cat aspirants like a well wisher.
Mad respect for him!!!!!!
Sir, can you please post some videos on practice questions for cubes and other LRDI sets
Sir love the way you teach and help us visualise so easily
but the question is saying the edge thats behind the right vertical edge , that should be the row that bottom cube is 25 right ?
sir amazing video ...but i m facing problems in solving practice questions on cubes
Hatts of to this Man
Sir we can try one more way to solve the question no 4 which is internal diagonal for that we have data as cube no 1 and last that is 125 we need to add both and divide by two we will get 63 the centre one again we add 1 and 63 divide by 2 we will get 32 and again we will add 63 and 125 and divide by 2 we will get 84 add all those we have our answer that is 315.
Thank you
In the first question. They have asked for the sum of the numbers of cubes which form the vertical edge of the larger cube behind the right edge of the front face of the larger cube. In the video sir has taken the cubes just behind the right vertical edge of the front face of the larger cube.
Are these cubes form the vertical edge of the larger cube?
I think the answer is no.
Does anyone have any ideas regarding this.
Thanks in advance.
Hi the question specifies that the smaller cubes form the vertical edge of the larger cube and we have to find the sum of cubes bebind the same. The behind cubes are just immediate.
Sir Practise ke liya Questions dete to ,
Sone pay suhaga hota😊
In q1 ..that cube is not forming edge of the larger cube as mentioned
It must be 4*25 Instead of 4*100 in the last part of the question, is it sir?
In 4 th question there is a difference of 31 which is 25+6 ...!