Bert sold 8 toy phones for $18 each, so he earned 8 * $18 = $144
Tory sold 7 toy guns for $20 each, so she earned 7 * $20 = $140
The difference in earnings between Bert and Tory is $144 - $140 = $4
#### 4
The answer is: 4
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
If Bert sold 8 toy phones for $18 each and Tory sold 7 toy guns for $20 each, what is the difference in earnings between Bert and Tory?

### Answer:
