human
There are 45 children in a classroom. One-third of them are girls. How many boys are in the classroom?
assistant
How many girls are there? ** One-third of all the kids are girls, which means 1/3 * 45 = <<1/3*45=15>>15 children.
How many boys are there? ** So there are 45 - 15 = <<45-15=30>>30 boys in the classroom.
#### 30