If the sum and difference of two numbers are 20 and 8 respectively, then the difference of their squares is · ABC26GN1703

Subject: General Aptitude · Chapter: Problems on Numbers

If the sum and difference of two numbers are 20 and 8 respectively, then the difference of their squares is

(a)12

(b)28

(c)160

(d)180

Answer

Answer (as printed): C

Explanation

Let the numbers be x and y. Then, x + y = 20 and x – y = 8. \ x2 – y2 = (x + y) (x – y) = 20 × 8 = 160.

Explanation as extracted from the printed page; notation may be imperfect.

Study loop for Problems on Numbers