Question

The unit digit in the product $122^{173}$ is

• A. 2
• B. 4
• C. 6
• D. 8

Answer 1

Answer:

A. 2

As we know a number with unit digit 2 have repeating cycle of 2,4,8,6 after every fourth power as power is 173 or (172+1) where till 172 , 43rd cycle will get complete and next unit digit will be 2