Can anyone offer some insight into the attached problem? My initial thought is that its all I, II and III since they are all factors of 450. I am a bit confused as to how n plays into the question?
Thanks
OA is B
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Which of the following must be an integer?
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shibal
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this question has been posted several times... a little research could be a good idea....
so, 450y=n^3, therefore 450 and Y must have triplets....
breakdown 450= 2*5*5*3*3.... which is equal to 2*5^2*3^2
for n^3, 450 must be multiplied by an integer that has 2, 5 and 3 to make all numbers squared to the third... threfore y must be 2^2*5*3....
hence the only integer in the options give is Y/2^2*5*3 (which would be equal to 1)....
so, 450y=n^3, therefore 450 and Y must have triplets....
breakdown 450= 2*5*5*3*3.... which is equal to 2*5^2*3^2
for n^3, 450 must be multiplied by an integer that has 2, 5 and 3 to make all numbers squared to the third... threfore y must be 2^2*5*3....
hence the only integer in the options give is Y/2^2*5*3 (which would be equal to 1)....
