Question

Fossil fuels are produced by the decay of organic material over millions of years. To make one gallon of gas, it takes about 98 tons of organic material, roughly the amount of wheat that could be harvested in a 40 acre field. Write an expression for the amount (in tons) of organic material it takes to make g gallons of gas. How many tons would it take to make enough gas to fill a car's 20 gallon gas tank?