Mario and Luigi were selling coupon books for the Video game club fundraiser. Apparently, Mario is a much better salesperson, because he sold 4 times as many coupon books as Luigi. If Luigi sold 12 fewer coupon books than Mario, what was the total number of coupon books the two boys sold?

the total number of coupon books sold is 20.

Step-by-step explanation:

Let x represent the number of coupon books that Mario sold.

Let y represent the number of coupon books that Luigi sold.

Apparently, Mario is a much better salesperson, because he sold 4 times as many coupon books as Luigi. This is expressed as

x = 4y

If Luigi sold 12 fewer coupon books than Mario, the expression would be

x = y + 12 - - - - - - - - - - -- -1

Substituting x = 4y into equation 1, it becomes

4y = y + 12

4y - y = 12

3y = 12

y = 12/3

y = 4

x = 4y = 4 × 4

x = 16

The total number of coupon books that the two boys sold is

4 + 16 = 20

answer: the first graph

step-by-step explanation: