Below is an instruction that describes a task. Write a response that appropriately completes the request in English. Please answer in English.

### Instruction:
There are 45 children in a classroom. One-third of them are girls. How many boys are in the classroom?

### Response:
45/3 = <<45/3=15>>15 children are girls.
There are 45-15 = <<45-15=30>>30 boys in the classroom.
#### 30