+0

# Units digit

0
32
2

What is the units digit of 3 to the 2004th power times 5 to the 2004th power?

Jul 8, 2022

#1
0

[3^2004 * 5^2004] mod 10^10 ==5087890625 - these are the last 10 digits.

Jul 8, 2022
#2
+2275
+1

Note that $$3^{2004} \times 5^{2004} = 15^{2004}$$

Because the base ends in a 5, the ones digit will always be $$\color{brown}\boxed{5}$$

Jul 9, 2022