What is the last digit of 5^2*9^4*4^3

Question

What is the last digit of 5^2*9^4*3

Answer 1

Last digit of 5^n is always 5.

Last digit of 9^n alternates between 9 and 1:

9, 1, 9, 1, ...

Last digit of 4^n alternates between 4 and 6:

4, 6, 4, ...

 

So to find the last digit, we take the product of each last digits,

5 * 1 * 4 = 20 whose last digit is 0. This is the last digit of the product.