Question

Find the remainder when $2^{87}$ is divided by 100

• A. 56
• B. 28
• C. 76
• D. 01

Answer 1

The correct option is B

28

Shortcut of last two digits:

When the question is about finding the remainder when you divide a number by 100, what we actually need to find out is the last two digits, for which we have a direct shortcut. For an indepth explanation, please refer the demo tutorial

$2^{87}=(2^{10}{)}^8\times 2^7$

$(2^{10}{)}^{evevpower}willalwaysendin..76$

$2^7$ ends in ...28

Therefore 76x...28=28