#14 Proportion with manipulating problem. #SAT, #ACT, #EST

14- Kiara uses her propane grill for an average of 11 hours each week. Her grill can run an average of 18 hours per 20-pound tank. Kiara would like to reduce her weekly expenditure on propane by $5. Assuming propane costs $ 16 per 20-pound tank, which equation can Kiara use to determine how many fewer average hours, h, she should use her grill each week?