If M and N are positive integers that have remainders of 1 and 3, respectively, when divided by 6, which of the following could NOT be a possible value of M+N?
(A) 86
(B) 52
(C) 34
(D) 28
(E) 10







Now M + N  = (Multiples of 6) + 1  + (Multiples of 6) +3 = (Multiples of 6) + 4 . Each of the the options should conform to this.

Divide the anwer options by 6 and if we can see that in A) 84/6 = 6*12 + 2....it would not be possible.
Ans : A