What is the remainder when the positive integer n is divided

Question

What is the remainder when the positive integer n is divided by the positive integer k,
where k > 1?
(1) n = (k+1)^3
(2) k = 5

masuhari · Answer

both n and k are positive.

dividing (1) by K, we get n/k = 3 + 3/k. Not sufficient enough to answer what the reminder is. So throw out choices A and D

with (2), we only know the value of k, so can't find out what the remainder is. So throw out choice B.

The 2 statements toegther give us n = (5+1)3 = 18 and k = 5. We can definitely say what the remainder is with the 2 statements together. So my pick Choice C

seofah · Answer

I thought, it was C as well, but OA isn't C!

gameCode · Answer

That is strange, I had thought it to be C as well. But there is one thing i have noticed. 
When k=2 remainder =1,
 k=3 r=0 
for k =>4 , r=3

But what difference does it make ! The QA c makes sense, else i has to be E.

seofah · Answer

There was a a small typo in the question

I got the answer that is in line with OA, but any attempts are welcome.

FN · Answer

I get A..

What is the remainder when the positive integer n is divided by the positive integer k,
where k > 1?
(1) n = (k+1)^3
(2) k = 5

2) insuff..

1) n= (K+1)(K+1)^2= (K+1)(K^2+2k+1)= K^3+3K^2+K+3K+1

as you can N= will always be 1 greater than K..

therefore 1 is the remainder...

1 is suff

marcap · Answer

A. You can pick k=2, k=3, k=4 and you'll see that the remainder is always 1.

x2suresh · Answer

agree with this solution

tusharvk · Answer

k=2,5 can be used to test. The remainder is always 1.
Rigorous proof is as follows:
n=k^3+3k^2+3k+1 
Remainder is clearly 1.
1 is sufficient and hence A.

What is the remainder when the positive integer n is divided

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