Question

Annie's car used 100 cups of gasoline during a drive. He paid $3.12 per gallon for gas. How much did the gas cost?

Answer 1

1 gallon = 16 cups

\[\frac{ 100 cups }{ 16 cups } = \frac{ x gallons }{ 1 gallons }\]

cross multiply and solve for x. this is the how many gallons 16 cups are.

multiply the number of gallons of gas by the price (3.12) to get the total amount paid.