Question

A,B,C and D are positive integers less than10.A is 3 times B and difference between B and D is 2, C is one less than D.Then which is the smallest?

Answer 1

A is 3 times B, thus B is smaller than A
B = A/3 
So B can be 1,2 or 3 as A is less than 10.

Difference between B and D is 2
D can be either B+2 or B-2.

If B=1 or 2, D will be B+2 (as B-2 is -1 and 0, but we know that D is a positive integer). C will be D-1 or B+1. So B will be smallest.

If B=3, then D will be either 1(B-2) or 5(B+2).
C is one less than D, thus C is smaller than D.
C is 0 or 4. But all are positive. So C is 4.
Hence B(=3) is the smallest.

Thus B is smallest.