Question

The smallest number that should be
added to or subtracted from the sum of
squares of 9 and 10 to make it a perfect
square is
(A) 1
(B) 15
(C) 5
(D) 12​

Answer 1

Answer:

12 (d) is the right option..

81+100= 181

181-12= 169

(169= 13^2)

12 ans.

Answer 2

Given:

First number = 9

Second number = 10

To Find:

Smallest number to be added to 9 and 10 so at to make a perfect square.

Solution:

Square of 9 = 81

Square of 10 = 100

Thus, sum of both numbers -

Square of 9 + Square of 10

= 81 + 100

= 181.

Now,

Next perfect square = 196 which is of 14

Previous perfect square = 169 which of 13.

Thus, the closest one is 169.

Difference = 181 - 169

= 12

Answer: The smallest number to be added to 9 and 10 so at to make a perfect square is 12.