Can you please make more videos on permutations and combinations.. the differences and how to distinguish the problems with respect to which concept would be used in which case
Questions that include words like, "arrangement," "display," "rank," or "order" are indicative of a permutation's question. Problems that ask about the number of ways you can combine, or create subgroups signal a combination's question.
9:22 Since the expression a/b + 1 can be expressed as (a+b)/c and since each unknown is one of the numbers 2, 3, or 5, you want the ----------- c/b denominator to be the smallest (2)of the three integers, hence (3 + 5)/2 = 4 . Hence the greatest possible value o expression is 4, answer
13:17 answer 17 A A B x B ----------- C B 5 B Only 1x1, 5x5, 6x6 will give you the same digit B B B 1 can be ruled out since 1 would give AAB (and not four digits CB5B), 5 can be also ruled out since 5 x a number 'n' would have to equal 3 (but 5 times a number 'n' equals 0 or 5). Hence B is 6. Need A to be number when multiplied by B (which is 6) will give 2 (either 6x7 or 2x 6). A is 7 hence 7 7 6 x 6- = 4 6 5 6 Hence A+B+C = 17 answer
Question that starts after 12:14: How can one assume it's B*B that resulted in 4 digit number, even if it was giving other product something to carry, the 4 digit number might be because of B*A.
In this case the only number we ruled out due to that issue was 1, and that's because it is not possibly to multiply a 3-digit number by 1 and get a 4-digit result. For example, 311 * 1 = 311. That will always be the case, and no numbers will carry over since the highest number, 9, multiplied by 1 is still 9. You won't get a result big enough that it needs carried. Hope that helps!
15:45 , B cant be 5 since A would have to be a unit digit that when multiplied by 5 = 3, but 5 times any number ends in either 0 or 5, hence A =5 has to be ruled out hence A =6
4:41 what is BC? the answer is 2 , 'statement 2 alone is sufficient to answer the question but statement one alone is not sufficient. one you chose this answer, you cannot choose the other choices since it contradicts the other 4 choices 1. you can't answer this question alone (all degrees) with statement one 2 yes you can answer the question with statement 2 alone since it is 90, 60, 30 degree triangle and in this instance BC=1 since AD=1 and since BC is one-half the length of AC and BC is one-half AC
1:15 angle E =45 since angle DAE =40 (parallel line and transversal) given that angle C from ACB =40 (75+65+40=180) hence 180- (40+95)=45 degree answer
For the hard arithmetics problem isn't B surely 6? I crossed out 5 because it was a known value in the answer (CB5B) where it would just be shown as B instead of 5. I am new to GMAT, so please correct me if I'm wrong. Thanks!
Hi Sajid! Erika showed us that for the problem we had BxB= a number that ends in B. So, she was going through the options quickly to show which ones would give us that result. Since 5x5=25, that is one option (25 ends in 5). And since 6x6=36, that is another option (36 ends in 6). Then, Erika began by plugging the 5 in for B in the problem. However, when she saw that 5A would have to equal a number that ends in 3, she could tell it wouldn't work out because no integer multiplied by 5 ends in 3. So, that's how she determined B = 6. Hope this helps a bit! Happy studying to you! :D
It's just mindblowing the clarity that you have when explaining
Erika is excellent one of the best experts out there. Her videos are very enjoyable
Hey Erika, Would you recommend us to solve the last problem during the GMAT at all -considering it took almost 3 mins to do it mentally?
Thanks a ton Erika. More such videos will help us in our preparation.
More will be coming! :)
Super helpful, looking forward to more such videos
Can you please make more videos on permutations and combinations.. the differences and how to distinguish the problems with respect to which concept would be used in which case
Questions that include words like, "arrangement," "display," "rank," or "order" are indicative of a permutation's question. Problems that ask about the number of ways you can combine, or create subgroups signal a combination's question.
9:22
Since the expression a/b + 1 can be expressed as (a+b)/c and since each unknown is one of the numbers 2, 3, or 5, you want the
-----------
c/b denominator to be the smallest (2)of the three integers, hence (3 + 5)/2 = 4 . Hence the greatest possible value o
expression is 4, answer
This is a brilliant video. Thank you Erika!
Glad you found it helpful! :)
I wouldn’t have been able to do the fourth one because I can’t remember how column multiplications work as I do mental calculations
Whatching this video. I know time management is going to be my nemesis.
Really helpful! Thank you!
You're very welcome! Glad you liked it, and thanks for stopping by :)
13:17 answer 17
A A B
x B
-----------
C B 5 B
Only 1x1, 5x5, 6x6 will give you the same digit B B B
1 can be ruled out since 1 would give AAB (and not four digits CB5B), 5 can be also ruled out since 5 x a number 'n' would have to equal 3 (but 5
times a number 'n' equals 0 or 5). Hence B is 6. Need A to be number when multiplied by B (which is 6) will give 2 (either 6x7 or 2x 6). A is 7
hence 7 7 6
x 6-
= 4 6 5 6
Hence A+B+C = 17 answer
Thank you very much. It was great. I solved all the question correctly before watched your answers.
thank you. you help me a lot. Nive and useful video
Hey there!
Would love to see a video of the strategies to tackle the hardest GMAT Algebra questions.
Question that starts after 12:14: How can one assume it's B*B that resulted in 4 digit number, even if it was giving other product something to carry, the 4 digit number might be because of B*A.
In this case the only number we ruled out due to that issue was 1, and that's because it is not possibly to multiply a 3-digit number by 1 and get a 4-digit result. For example, 311 * 1 = 311. That will always be the case, and no numbers will carry over since the highest number, 9, multiplied by 1 is still 9. You won't get a result big enough that it needs carried. Hope that helps!
@@MagooshGMAT What if c = 0 ? Then we get 3 digit number. I think we have to expect every possibility
15:45 , B cant be 5 since A would have to be a unit digit that when multiplied by 5 = 3, but 5 times any number ends in either 0 or 5, hence A =5 has to be ruled out hence A =6
In general it cant be 5 because there is already a 5 under the line
@@nicoleweigelt3938 Yes, you are correct
4:41
what is BC?
the answer is 2 , 'statement 2 alone is sufficient to answer the question but statement one alone is not sufficient.
one you chose this answer, you cannot choose the other choices since it contradicts the other 4 choices
1. you can't answer this question alone (all degrees) with statement one
2 yes you can answer the question with statement 2 alone since it is 90, 60, 30 degree triangle and in this instance BC=1 since AD=1 and since
BC is one-half the length of AC and BC is one-half AC
Hi,where have got math example of GMAT?Can you say?
The question starting at 12:22. Is it a confirmed 700 question? It seems to me as if it takes like very much time to come up with the right solution
Hi Itachi, yes, this is a Very Hard question, and our Very Hard questions tend to fall within the 700+ range.
1:15
angle E =45 since angle DAE =40 (parallel line and transversal) given that angle C from ACB =40 (75+65+40=180) hence 180- (40+95)=45 degree answer
question to someone who has taken the gmat: how comparable in difficulty are these hard questions?
For the hard arithmetics problem isn't B surely 6? I crossed out 5 because it was a known value in the answer (CB5B) where it would just be shown as B instead of 5. I am new to GMAT, so please correct me if I'm wrong. Thanks!
Good thinking! :D
helpful thanks.
excellent
🙌
nice questions. Surprisingly, the US GMAT score in 2019 was lower that the world's average.
not surprising
I have exam after 1 week how can get touch with you
You can always reach us by using the 'help' button on any Magoosh page, or by writing to us at help@magoosh.com!
Is GMAT that easy or these are just but simple questions?
Hi, Erika. My answer to the last question is 15. The solution is B=6, A=2, and C=1 (total sum of 15). It's different from the answer you got.
Your set of values is incorrect. You can the try multiplication to find out. Correct ans is 17.
Sorry, But I did not understand that why the number 5 and 6 was choosen and then only 6 for the B
Hi Sajid! Erika showed us that for the problem we had BxB= a number that ends in B. So, she was going through the options quickly to show which ones would give us that result. Since 5x5=25, that is one option (25 ends in 5). And since 6x6=36, that is another option (36 ends in 6). Then, Erika began by plugging the 5 in for B in the problem. However, when she saw that 5A would have to equal a number that ends in 3, she could tell it wouldn't work out because no integer multiplied by 5 ends in 3. So, that's how she determined B = 6. Hope this helps a bit! Happy studying to you! :D
genius
As a competent math student, I was able to answer all the questions correctly in no time. Are GMAT math problems really at that easy of a level?
The Quant section tests different concepts, try taking a diagnostic quiz or test to get a better sense! We have a free diagnostic on our GMAT blog.
It needs to be solved under 2 minutes. Every one can solve untimely manner.
question no. 2 was solved in less than two minutes.
The question "if BC=BD..." is solved from around 4 minutes to minute 9 in the video. :-)
I'm 17 and i got the hard arithmetic one in like 3 min. GMAT dosent seem that tough. I'm from India btw
Well done, Anuj! 😃
come back in 10 years 😔
But do you get any bches? That's what I thought, it's already over for you lil bro 🥱
Okay anju did you score high?
These are very easy compared to cat
you really call that hard ?
You want a cookie or a medal?
Okay tough guy