Answer:
Step-by-step explanation:
We need to do several things. I'll put all the steps separate, so you easily follow.
40 + 40 = 80
$80 + s < $125
s < $45
45/15 is 3, so he can buy 3 shirts.
$80 + $45 < $125
$125 < $125 ✔
This is an inequality. To make sure we got it right, we need to try another value.
$80 + $32 < $125
$112 < $125 ✔
s < $45
3 shirts
I'm always happy to help :)