Liz recently took a road trip She bought 30 gallons of gasol

Liz recently took a road trip. She bought 30 gallons of gasoline for $3.18 per gallon and 10 gallons at a price of $3.75 per gallon. She filled her tank once on the way back with 20 gallons at $3.65 per gallon. What was the average cost of fuel, per gallon, on her trip? For the first four hours on his delivery route, a trucker drove at an average of 40 mph. For the next 6 hours, which completed his route, he averaged 55mph. What is the average speed for the whole trip? You want to rent a car for your coming vacation and you\'ve checked out two car rental agencies. The first charges a flat fee, per day of $55. The second charges $10 per day plus 20 cents for each mile you drive. If you think that you\'ll drive an average of 150 miles a day during your vacation, which car rental should you choose to spend the least amount of money? Explain your reasoning. What if you estimate that you\'ll drive an average of 300 miles per day during your vacation? Then which car rental is less expensive? Again, explain your reasoning.

Solution

2) She filled 30 gallons for $ 3.18 per gallon , so, total price = 30*3.18 = $ 95.4

10 gallons for $ 3.75 gallons , so total price = 10*3.75 = $ 37.5

On return 20 gallons for $3.65 per gallon = 20*3.65 = $ 73

So, Total cost of fuel = $ (95.4 + 37.5 + 73 ) = $ 205.9

Total gallon = 60 gallons

So, Avg cost of fuel per gallon = Total cost of fuel/total gallons = 205.9/60

= $ 3.43