shashankism wrote:
amathews wrote:
What is the remainder when 5^68 is divided by 7?
A) 1
B) 2
C) 3
D) 4
E) 6
We can do it by expanding the number .. {} remainder value in the below explanation
{5^68 / 7}= {25^34 /7} = {4^34 /7} = {16^17 /7 } ={2^17/7} = {((2^3)^5 * 2^2) /7} = {((8)^5 * 2^2) /7} = 1 * 4 = 4
So Remainder is 4.
This can also be solved by following method .. Considering -ve values in expansion.
{5^68 / 7} = {-2^68 /7} = {2^68 /7 } = {8^22*2^2/7} = { 4/7 } = 4
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