Maria bought seven boxes. A week later half of all her boxes were destroyed in a fire. There are now only 22 boxes left. With how many did she start?

Maria started with 37 boxes.

Given:

7 boxes bought

half of the boxes were destroyed in the fire.

22 boxes left

Find the beginning number of boxes.

Let x be the beginning number of boxes.

(x + 7) / 2 = 22

2 ((x+7) / 2) = 2 (22)

x + 7 = 44

x = 44 - 7

x = 37

To check:

x + 7 = 37 + 7 = 44

44 * 1/2 = 22

22 = 22