The sum of two numbers is 25 and their differenee is 13. Find their product :

A. 104
B. 114
C. 315
D. 325

Let the numbers be x and y. Then, x + y = 25 and x – y = 13.
4xy = (x + y)2 – (x – y)2 = (25)2 – (13)2 = 625- 169 = 456
=> xy = 114.