Question

roys car gets an average gas mileage of 29mi/gal. Roy starts his trip with 12 gal of gas.How many gallons of gas are left after a 140 mile trip?(only an algebraic solution can receive full credit)

Answer 1

The answer is 208. The equation to get this is m=29g-140 where m is miles and g is the gallons. Plug 12 in for g and solve for m. 29 * 12 = 348, 348-140 = 208. Therefore, m=208.

Answer 2

You can use a ratio to solve this.

29/1 = 140/x

Cross multiply

29x = 140
x = about 4.8 gallons after the trip