Let's call x the price of a box of slime.
Gianna spent 4 × $58 for art supplies so 4(58) + 8x all together. We have
392 ≤ 4(58) + 8x ≤ 472
We can work with both inequalities at once. 4(58)=232 so we subtract that from all three sides.
160 ≤ 8x ≤ 240
Divide all three sides by 8, a positive number so the inequalities don't flip.
20 ≤ x ≤ 30
Answer: Least: $20, Most: $30
