Hello Dyaneese
Since each shirt cost the same amount,
let x = full price of each shirt
x-3.66 = discounted price of each shirt
Since John bought 3 shirts, so his cost for all 3 can be represented by the following equation:
3(x-3.66) = 62.31
We can solve this equation for x, the full price of a single shirt before the discount or taxes.
First distribute the 3
3x-10.98 = 62.31
Add 10.98 to both sides
3x = 73.29
Divide by 3
x = 24.43
Each shirt cost $24.43 before discount