Chapter 2 - Solving Equations - 2-2 Solving Two-Step Equations - Practice and Problem-Solving Exercises - Page 91: 23

16 boxes

Let x be the number of boxes. Each one is 50 pounds, so we must multiply x by 50 to get the total weight. The weight of the person is 160, and the max for the elevator is 1000. The equation becomes 50x+160=1000. Subtracting 160 to isolate x, we get 50x=840. Dividing by 50 to solve for x, we get 16.8. Since boxes are whole, it must be 16 with space left over.