You are getting ready to make a 640-mile car trip. in general, your car can
drive 160 miles on 5 gallons of gasoline. how many gallons of gasoline will you use for the trip? you started out with 4 gallons of gasoline in your car and gasoline is
$2.29 per gallon. how much money will you spend on gasoline on the trip?

You will need to purchase 16 more gallons that cost $2.29 each for your final amount to be $36.64

Step-by-step explanation:

You need to find how many miles you can get per gallon to use 160 miles on 5 gallons.

 =   .  Meaning your unit rate for this would be 32 miles for 1 gallon

You then need to find out how many gallons you will need if you're going to 640 miles and get 32 miles per gallon.

 =  20

Meaning you will need 20 gallons.

Now since you already know how many gallon you have which is 4. Then you know how much you need, 20 - 4 = 16

Then since they will be $2.29 each, multiply 2.29 by 16 to get $36.64

Meaning you will need to 16 gallons costing 2.29 each and you will spend $36.64 dollars on the trip