mgmat cat 4b minimum number

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mgmat cat 4b minimum number

by vkb16 » Thu Mar 12, 2009 5:09 am
Susie can buy apples from two stores: a supermarket that sells apples only in bundles of 4, and a convenience store that sells single, unbundled apples. If Susie wants to ensure that the total number of apples she buys is a multiple of 5, what is the minimum number of apples she must buy from the convenience store?

Choices--0, 1, 2, 3, 4, 5

OA is 0

how can this be? Im for 1
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by scoobydooby » Thu Mar 12, 2009 5:13 am
0 is a multiple of all numbers and factor of none. 0 is the minimum multiple

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by Ian Stewart » Thu Mar 12, 2009 5:38 am
She could buy, for example, 5 bundles of four apples from the supermarket, and no single apples from the convenience store, giving her 20 apples in total.
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by vkb16 » Sun Mar 15, 2009 9:25 pm
thanks Ian, but why cant we assume she buys just 1 set of 4 apples?
why are we assuming she goes for a multiple of 5?

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by m&m » Mon Mar 16, 2009 6:34 am
Susie needs a multiple of 5, so either:
x = 5,10,15,20,25...

we want to miminize C in equation x = 4S+C

since we are asking to minimize C, the smallest C we can have is 0. Can we get C=0 from above...

if we choose x=20 then S=5 and C=0


so... we managed to minimize C with 20 apples and hence C=0

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plz correct me

by vamshi294 » Mon Mar 16, 2009 9:41 am
Hi All,

From the question 'Susie can buy apples from two stores' ; susie CAN buy from two stores, but it is not given that it is mandatory to purchase from both the stores... and the question is 'she buys is a multiple of 5, what is the minimum number of apples she must buy from the CONVENIENCE store?'.... how many we can buy from CONVENIENCE store alone to make it a multiple of 5....so i believe answer is straight and it is '5'.

Please correct me, if i am wrong.


Mr. scoobydooby, from definition of multiple, 0 is not considered multiple of any number