Question

The last digit of 2137${}^{753}$ is

• A. 9
• B. 7
• C. 3
• D. 1

Answer 1

The correct option is B 7

The last digit of 2137${}^1$ is 7
Last digit of 2137${}^2$ is 9. Last digit of 2137${}^3$ is 3, the last digit of 2137${}^4$ is 1, last digit 2137${}^5$ is 7 the last digit of 2137${}^6$ i 9 and so on. Hence it form a pattern and the last digit repeats for every 5th. 753$=$ 4 $\times$ 188 + 1. Thus the last digit of 2137${}^{753}$ is the same as that of 2137${}^1$ i.e. 7.

Hence option (2) is correct.