I got this only math homework and I really need help solving it. This is what it says: Bryan bought a new battery-gasoline hybrid car. On a trip the car ran exclusively on its battery for the first 40 miles, and then ran exclusively on gasoline, using gasoline at a rate of .02 gallons per mile. On the whole trip he averaged 60 miles per gallon. How long was the trip in miles?
Let x = the answer, the number of miles long the trip was.
Then x-40 = the number of miles the car went on gasoline.
Then .02(x-40) = the number of gallons used on the whole trip
x miles 60 miles
----------------- = ------------
.02(x-40) gallons 1 gallon
Cross multiply
60(.02)(x-40) = x
1.2(x-40) = x
1.2x-48 = x
.2x = 48
x = 240
240 miles.
Edwin