Question

Given

A A A

+ A A

--------------

A B B

If A is multiple of $2,$ what could be the value of B ?

• A. $0$
• B. $8$
• C. $4$
• D. $4$ or $8$

Answer 1

Answer: (D)

$4$ or $8$

A A A
+ A A
A B B
Which means no carry over, thus A will be smaller than 5 and hence B will be smaller than 9.
If A is a multiple of 2, then A could be 0 or 2 or 4. But A cannot be 0.

So, A could be 2 or 4. and hence, B (= A + A) = 4 or 8.

So, option D.