Answer:
He can by for sets, that is, 24 baseballs and 12 batting helmets.
Explanation:
We know that
Each baseball costs $2.25.
Each helmet costs $22.50.
This mean that 8 baseballs costs:

And all 3 batting helmets costs:

Now, one set of 8 baseballs and 5 helmets costs

If coach Shaw has $400, the total number of set he can buy is

This means he can by for sets, that is, 24 baseballs and 12 batting helmets.