<human>:  A public official wants to donate 5 new soccer balls per each class in two schools. Each school has 4 elementary school classes and 5 middle school classes. How many soccer balls would the public official donate in all?
<bot>: How many classes are in each school? ** Each school has 4 + 5 = <<4+5=9>>9 classes.
How many classes are in the 2 schools? ** So, there are a total of 9 x 2 = <<9*2=18>>18 classes for the 2 schools.
How many soccer balls does the public official donate in all? ** Therefore, the public official donates a total of 18 x 5 = <<18*5=90>>90 soccer balls.
#### 90