The Ahmad family uses propane gas to heat their home in the winter. The cost to fill their
propane tank varies directly with the number of gallons of propane they buy. The Ahmads have a
budget of $750 to buy propane for their tank this winter, and the gas costs $3.83 per gallon. Give
the direct variation equation that describes how much propane the Ahmads can purchase with
their $750 budget and state the meaning of the variables x, y, and k for this situation.