Question

The digit in unit place of $12^{21}$ + $15^{37}$ is:

• A. 7
• B. 5
• C. 4
• D. 6

Answer 1

Answer:

A. 7

Divide the power 4 and write remainder in the place of power. Unit digit of 12^21 + 15^37 ⇒ 12^1 + 15^1 ⇒ 2 + 5 ⇒ 7