Sajjad1994
What is the remainder when the positive integer N is divided by 2?
(1) If \(N^2\) is divided by 2, the remainder is 1.
(2) If N is divided by 4, the remainder is 3.
From the question stem, we get :
N is a positive Integer.
We have to find the value of rem(N/2).
Consider first stem :
(1) If \(N^2\) is divided by 2, the remainder is 1.
\(REM[\frac{{n^2}}{2}]\) = 1
Take a few examples :
n = 2 ;\(n^2\) = 4 ; rem = 0.
n = 3 ; \(n^2\) = 9 ; rem = 1.
So we can safely say that N is odd.
From this we can conclude that \(REM[\frac{{n}}{2}]\) will also be 1.
Cancel B,C,E.
(2) If N is divided by 4, the remainder is 3.
Now independently consider stem 2 :
\(REM[\frac{{n}}{4}]\) = 3
From this think of a few basic numbers, and you will conclude that it is possible only when N is of the kind 7,11,15 etc or simply of the kind 7 + (n-1)4 where n = {1,2,3,4,......n}
Note 7 be odd, while (n-1)*4 will always be even. even + odd = odd.
From this we can conclude that N will be Odd and thus \(REM[\frac{{n}}{2}]\) will also be 1.
Cancel A.
IMO D.