Maria works at a bookstore. on wednesday, she sold three times as many books as she did on tuesday. on thursday, she sold 8 fewer books than she did on wednesday. during the three days, maria sold 20 books. create an equation that can be used to find m, the number of books maria sold on tuesday.

To write an equation to show how many books Maria sold on Tuesday, you will write an equation for each day.

Tuesday - m
Wednesday - 3m
Thursday - 3m - 8

Show all of these in an addition problem with a total of 20 and simplify.

m + 3m + (3m - 8) = 20

7m - 8 = 20; You can solve this equation to find the number of books Maria read.