b. C = 5 × ($0.75 × 4)
Step-by-step explanation:
Note that 4 quarts = 1 gallon
Therefore, if a cleaning product sells for $0.75 a quart, the equation can be used to solve for the total cost, C , of five gallons of the product will be:
= 5 × ($0.75 × 4)
= 5 × $3
= $15