### Instruction: Which of the following must be subtracted from 2^72 so that the resulting integer will be a multiple of 3?
Answer Choices: (A) 5 (B) 4 (C) 1 (D) 3 (E) 2.### Response: Let's think about the multi-choice question step by step.
{4^1} / 3 =4/3 remainder 1
{4^2} / 3 = 16/3 remainder 1
{4^3} / 3 = 64/3 remainder 1
{4^4} / 3 = 256/3 remainder 1
Actually the same remainder keeps repeating .....
Try with a diff no, say 2
{2^1}/3 = remainder 2
{2^2}/3 = remainder 1
{2^3}/3 = remainder 2
{2^4}/3 = remainder 1
The answer is C