Question

Write the possible unit’s digits of the square root of the following numbers. Which of these numbers are odd square roots?
(i) 9801
(ii) 99856
(iii) 998001
(iv) 657666025

Answer 1

(i) 9801

Since, unit digit of 9801 is 1

\(\therefore\) Unit digit of square root = 1 or 9

Since the number is odd, square root is also odd

(ii) 99856

Since, unit digit of 99856 = 6

\(\therefore\) Unit digit of square root = 4 or 6

Since the number is even, square root is also even

(iii) 998001

Since,unit digit of 998001 = 10

 \(\therefore\) Unit digit of square root = 10 or 9

Since the number is odd, square root is also odd

(iv) 657666025

Since, unit digit of 657666025 = 5

\(\therefore\) Unit digit of square root = 5

Since the number is odd, square root is also odd