Question

2. A toy store worker packed two boxes of identical dolls and plush toys for shipping in boxes that weigh 1 oz when empty. One box held 3 dolls and 4 plush toys. The worker marked the weight as 12 oz. The other box held 2 dolls and 3 plush toys. The worker marked the weight as 10 oz. Explain why the worker must have made a mistake.

Answer 1

3D+4P=11
2D+3P=9

The solution to this system is not possible: plush toys weigh 5 oz. and dolls have a negative weight.

Answer 2

Plush toys weigh 5oz and dolls weigh a negative number.