The sum of two number is 25 and their difference is 13. Find their product.

Let two number be $x$ and $y$

$x+y=25$            …… (1)

$x-y=13$            …….. (2)

On solving equations (1) and (2), we get

$2x=38$

$x=19$

$y=6$

Since, the product of these two numbers

$=19\times 6$

$=114$

Hence, this is the answer.