Question

What could be the possible ‘one’s’ digits of the square root of each of the followingnumbers?(i) 9801              (ii) 99856            (iii) 998001          (iv) 657666025

Answer 1

(i) `9801` - Here, the last digit is `1`. So, its square root can have `1` or `9` as its unit digit.
(ii)`99856` - Here, the last digit is `6`. So, its square root can have `4` or `6` as its unit digit.
(iii) `998001` - Here, the last digit is `1`. So, its square root can have `1` or `9` as its unit digit.
(iv) `657666025` - Here, the last digit is `5`. So, its square root can have `5` as its unit digit.