Question

The square root of 121 can be confirmed after repeated subtraction of the starting _______ odd numbers.

• A. 8
• B. 9
• C. 10
• D. 11

Answer 1

The correct option is D 11

121 - 1 = 120
120 - 3 = 117
117 - 5 = 112
112 - 7 = 105
105 - 9 = 96
96 - 11 = 85
85 - 13 = 72
72 - 15 = 57
57 - 17 = 40
40 - 19 = 21
21 - 21 = 0
So, we get 0 after repeated subtractions of 11 successive odd numbers. Hence, The square root of 121 can be confirmed after repeated subtraction of the starting 11 odd numbers.