Step-by-step explanation:
The total pounds of apples Marc has = 36
The number of pounds required for each pie = 4
The number of pies made from 36 pounds = [tex]\frac{36}{4}[/tex] = 9 pies.
The cost of one eapple pie = $8
Cost of 9 pies = 9 (8) = $72
Marc collects $72 for all of the pies