Question

what is the remainder when 4^31 is divided by 10

Answer 1

Hold on, sorry. Let me try and see if I can solve this..

Answer 2

Answer: 4
This can be done with or without a calculator.

Calculator method:
Punch it into a calculator and see what the remainder is.

Without calculator:
Investigate power of 4 and the remainder when it is divided by 10.
4^1 = 4 (the remainder is 4)
4^2 = 16 (the remainder is 6)
4^3 = 64 (the remainder is 4)
4^4 = 256 (the remainder is 6)
This pattern continues. If the power is odd, then you will get a remainder of 4.