If Micah has 7 fish, and Kenneth has three times as many fish, then Kenneth has 7 x 3 = 21 fish.
If Matthias has 15 less fish than Kenneth, then Matthias has 21 - 15 = 6 fish.
The total number of fish that the boys have is 7 + 21 + 6 = 34 fish.
#### 34
The answer is: 34
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
If Micah has 7 fish in his aquarium, Kenneth has three times as many fish, and Matthias has 15 less fish than Kenneth, what is the total number of fish that the boys have?

### Answer:
