Question

The rightmost non-zero digit of the number ${30}^{2720}$ is?

• A. 1
• B. 3
• C. 7
• D. 9

Answer 1

The correct option is A 1

Rightmost non-zero digit of ${30}^{2720}$ must be the unit digit of $3^{2720}$
As ${30}^{2720}=3^{2720}\times {10}^{2720}$
Unit digit of $3^{2720}$ is 1.