If the sum of two numbers is 30 and their difference is 8, what is their product?

Let the two numbers be x and y respectively.

According to the question ;

x + y = 30   ….(i)

x – y = 8    …. (ii)

Adding equations (i) and (ii),

⇒ x + y + x – y = 30 + 8

⇒ 2x = 38

⇒ x = 

⇒ x = 19

Now, substituting the value of x in equation (i), we get ;

x + y = 6

⇒ 19 + y = 30

⇒ y = 30 – 19

⇒ y = 11

Hence, the required numbers are 19 and 11 respectively.

Their product = 19 * 11 = 209