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how to answer this question? percentage increases Watch

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    hi guys!

    im a bit stuck on how to approach this question and im literally just trying anything. im trying to work out the percentage change through using 1.2 as a representation of a 20% increase in each of the numbers, although I don't really know where I'm going with, I've attempted this question quite a few times using this logic but get different answers each time (none of which are accurate)

    also I've already checked, the answer is definitely not G any help would be greatly appreciated! thank you! Attachment 693922693924Name:  image.jpg
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    Do u know what the right answer is. I got 44% but i just wanna check before i divulge how i got there
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    Ask Diane Abbott, I am sure she can help!
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    In the first place the numerator of both fractions should be multiplied by 1.2*1.2*1.2 as a , b , c ,d each individually increase by 20% so you have new a = 1.2 old a
    new b = 1.2 old b and so on then you just need to simplify both fraction by 1.2 and use the remaining 1.2*1.2 (1.44) as a common factor and you get that the new value of the sum is the old one * 1.44 so the sum increased by 44%
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    thank you for the answers received

    i've attempted the method in the reply above but for some reason, i still don't fully understand how to work out the answer and obtain 44%. it's just not going into my mind!
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    (Original post by ashaxo99)
    thank you for the answers received

    i've attempted the method in the reply above but for some reason, i still don't fully understand how to work out the answer and obtain 44%. it's just not going into my mind!
    I'll give you the details in this instance.

    Lets start with:

    \displaystyle \frac{abc}{2d}+\frac{3bcd}{a+b+c  }

    Each variable is increased by 20%, which is equivalant to multiplying it by 1.2.

    So, our new formula is:

    \displaystyle \frac{(1.2)a(1.2)b(1.2)c}{2(1.2)  d}+\frac{3(1.2)b(1.2)c(1.2)d}{(1  .2)a+(1.2)b+(1.2)c}

    We can cancel 1.2 in the numerator and denominator of each to get.


    \displaystyle \frac{a(1.2)b(1.2)c}{2d}+\frac{3  b(1.2)c(1.2)d}{a+b+c}

    And now pull out the common factor from each, giving.

    \displaystyle (1.2)^2\left[\frac{abc}{2d}+\frac{3bcd}{a+b+c  }\right]

    So, our new value is (1.2)^2 = 1.44 times our old value, or an increase of 44%.
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    (Original post by ghostwalker)
    I'll give you the details in this instance.

    Lets start with:

    \displaystyle \frac{abc}{2d}+\frac{3bcd}{a+b+c  }

    Each variable is increased by 20%, which is equivalant to multiplying it by 1.2.

    So, our new formula is:

    \displaystyle \frac{(1.2)a(1.2)b(1.2)c}{2(1.2)  d}+\frac{3(1.2)b(1.2)c(1.2)d}{(1  .2)a+(1.2)b+(1.2)c}

    We can cancel 1.2 in the numerator and denominator of each to get.


    \displaystyle \frac{a(1.2)b(1.2)c}{2d}+\frac{3  b(1.2)c(1.2)d}{a+b+c}

    And now pull out the common factor from each, giving.

    \displaystyle (1.2)^2\left[\frac{abc}{2d}+\frac{3bcd}{a+b+c  }\right]

    So, our new value is (1.2)^2 = 1.44 times our old value, or an increase of 44%.
    woah, so it really was this simple after all! it feels so good to finally understand this - thank you so much for the help!
 
 
 
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