divisibility

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divisibility

by Gurpinder » Mon Jul 11, 2011 6:12 am
hey,

In the book it says follow [spoiler].12y=9[/spoiler] but I want to ask you experts whether my way is ok too:

x/y = 96.12 --> .12(100) --> 12/100 --> 3/25

So the remainder is 3 or a multiple of 3 and the divisor is 25 or a multiple of 25.

Since the questions says the remainder is 9 which is 3 times the remainder I got from the above fraction (3/25) I would have to multiply 25 by 3 as well to get what y equals which is [spoiler]75. Hence the right answer. But is my method ok?[/spoiler]



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by testprepDublin » Mon Jul 11, 2011 6:31 am
There is nothing wrong with your method but there is a simpler way to do it.

Since we know x/y=96.12 and we know the remainder is 9, we can find the denominator (y) by dividing 9 by 0.12 which gives 75. The answer is B.
Deirdre at testprepdublin.com

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by Gurpinder » Mon Jul 11, 2011 10:11 am
k thx.
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.