Problema Solution

the gas price index in 1985 was 213.3 and the gas price index for 200 was 273.6. if it costs $16.84 to fill up your gas tank in 1985, how much would it be to fill up the same tank in 2000?

Answer provided by our tutors

213.3/16.84 = 273.6/x (Cross multiply!)

213.3x = 4607.424 (This is what you end up with when you cross multiply.  Now divide both sides by 213.3

x = 21.60  (The total is $21.60)