When the smaller of two consecutive integers is added to four times the larger the result is 79. What is the product of the two integers?

So, let's define what "two consecutive integers are": 4 and 5, 5 and 6, 6 and 7 ...

This would be written as "x" and "x+1".

So:

x + 4 * (x+1) = 79

x + 4x + 4 = 79

5x = 79 - 4

5x = 75

x = 75/5

x = 15

The product:

15 * (15+1) = 15 * 16 = 240