the answer:
the total distance of the trip is 821 miles from home,
for this the car gets 24 miles per gallon
the average price of gas is $3.74 per gallon
the price can be calculated as:
for the trip,
24 miles-------------1 gallon
821 miles------------ x= 821/24=34.20 gallons
1 gallon------------- $3.74
34.20 gallons---------x=?
to find this value
34.20 gallons x $3.74 = $127.93.