Question

Suppose that every car on the road burned up about two gallons of gas a day. For each gallon of gas burned, one pound of carbon dioxide is released into Earth’s atmosphere. If 144 million cars are used in the United States each day, how many pounds of carbon dioxide are released into the air each week?

Answer 1

You want to find pounds of CO2 / week = lb CO2 / week



1 lb CO2 2 gal gas 144 * 10^6 car 7day
------------- x --------------- x ------------------ x ---------
1 gal gas car day week



Check what happen with units

lbCO2 gal car day
----------- x ------ x ------ x ------- = lb CO2 / week
gal car day week


So the result is 2 * 144 * 10^6 * 7 lb CO2 / week = 2,016 - 10^6 lb CO2 / week


Answer: 2,016 millions of pounds of CO2 per week.