Why is Dividing by a Fraction Equivalent to Multiplying by the Reciprocal?

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  • Опубліковано 3 гру 2024

КОМЕНТАРІ • 22

  • @no_non-sense
    @no_non-sense 10 місяців тому +1

    This is the best explanation I have found to understand the concept. One of my tutoring students asked why the reciprocal is used when dividing a fraction and I had no clue. I read/watched many explanations and I was totally confused. The lightbulb came on while watching this video. Now I can confidently give an answer to my student. Thank you!!!

    • @Mathispower4u
      @Mathispower4u  10 місяців тому

      That is great to hear! I appreciate you leaving your comment.

  • @icyspring4295
    @icyspring4295 3 роки тому +2

    Really helped me visualise why this works (multiply denominator by reciprocal in order to get 1 so the problem can be simplified later, multiply numerator in order to maintain equality). Thanks!!

  • @switchfan_
    @switchfan_ 2 роки тому +3

    That was INCREDIBLY helpful, as I now understand WTF is actually happening. Thank you!

    • @Mathispower4u
      @Mathispower4u  2 роки тому +1

      I am glad the video helped you understand better. :)

  • @rendydddd
    @rendydddd 4 роки тому +4

    For those who who did not get it
    In example a/b ÷ c/d is equivalent to a/b × d/c, the rest is explanation why
    For example, everything devided by 1/6 is going to be 6×bigger, that means everything miltipled by 6/1 is also going to be 6×bigger, that's it
    You can also do it like this -> b/a ÷ c/d = b÷c/d÷a

  • @Insomnia_Animations
    @Insomnia_Animations 10 місяців тому

    wowowow! such nice explanation!!!! thank you very much for helping people who want to understand, understand!

  • @olgavolga8936
    @olgavolga8936 Рік тому

    Thank you! It was extremely helpful for my 6th grader to understand how this works

    • @Mathispower4u
      @Mathispower4u  Рік тому

      I am happy to hear the video helps. I appreciate you leaving a comment. :)

  • @syafihakim1181
    @syafihakim1181 2 роки тому +1

    For those who are still wondering why do you need the reciprocal. I GOT YOU!
    One of the definitions of division is :
    10 balls divided by 5 boys, how many balls does each boy get?
    Answer : 2. 10 balls are for 5 boys. 2 balls for each.
    6 oranges divided by 2 girls, how many oranges does each girl get?
    Answer : 3. 6 oranges are for 2 girls. 3 oranges for each.
    ------ The goal here is to find out how many of something (numerator) does EACH(denominator) get! The EACH in this sentence is equivalent to 1 in Math. ------
    The definition maintains for any type of division.
    10 balls divided by 0.5 boy, how much will 1 boy get?
    Answer : Well, if 10 balls are for 0.5 boys, then it would be 20 balls for 1 boy.

  • @samuelfrade2652
    @samuelfrade2652 2 роки тому

    How about this? In general a ÷ b × b = a. Because multiplying by something after dividing by that same thing does not change the number. Now we have a/b ÷ c/d × c/d = a/b. But we also have a/b × d/c × c/d = a/b. So this yields a/b ÷ c/d × c/d = a/b × d/c × c/d and this gives a/b ÷ c/d = a/b × d/c.

  •  2 роки тому

    I’m astonished. Thanks!

  • @rendydddd
    @rendydddd 4 роки тому

    Thanks, this was really helpfull

  • @Tonixy4
    @Tonixy4 6 років тому

    I get it now !! Thank you

  • @tomcass240
    @tomcass240 5 років тому +6

    so you're going to explain how dividing by a fraction is equivalent to multiplying by the reciprocal by simply doing exactly that? where was the explanation?

    • @strafer8764
      @strafer8764 4 роки тому

      I’m wondering the same thing.

    • @tomcass240
      @tomcass240 4 роки тому +1

      ​@@strafer8764 Yeah this isn't a good video but I think I understand it. If you think about it in decimals it makes more sense. 1/4 divided by 3/8 is the same as saying 1/4 divided by 0.375. And 3/8 divided by 1/4 is the same as saying 0.375 times by 1/4. Multiplying by a decimal naturally will give you the same answer as dividing by the fraction, as a fraction is simply a decimal in a different form.

    • @rekhapandey3941
      @rekhapandey3941 3 роки тому +1

      @@tomcass240 bro i just got its explanation
      Say 1/2 / 1/4 means 0.5 / 0.25 here according to reciprocal we should do 1/2 * 4/1 = 4/2 = 2 and in decimal it is 0.5 / 0.25 = 2 because we when we divide then we read table and in table of 0.25 * 1 = 0.25 and 0.25 * 2 = 0.5 hence we can simply do reciprocal of it

    •  2 роки тому

      I actually found this video astonishing, and it gives the proof why and how it works.
      However I’ll leave here a reasoning that will help you understand the logic behind this.
      Let’s say you are dividing 30 by some numbers:
      30/5 = 6
      30/3 = 10
      30/2 = 15
      30/1 = 30
      Can you notice a pattern?
      The lower the number you divide a number for, the larger de product, so what do you think is the product of *30/0.5*?

  • @JeremyFtw4
    @JeremyFtw4 6 років тому +7

    You didnt explain WHY it works you just showed a different way of solving those types of problems....

    • @bleemma
      @bleemma 6 років тому +5

      It works because of the principle that everything you do to the denominator, you must do to the numerator. In this case, when you multiplied the denominator by 8/3 to get it to one whole (thereby getting rid of the complex fraction), you did the same thing to the numerator. Voila- the numerator (original dividend) is now multiplied by the reciprocal of the original divisor.