Question 164348
 A forester mixes gasoline and oil to make 2 gallons of mixture for his two-cycle chain-saw engine. This mixture is 32 parts gasoline and 1 part two-cycle oil. How much gasoline must be added to bring the mixture to 40 parts gasoline and 1 part oil?
:
Convert the mixtures to percent oil (decimal equiv):
{{{1/((32+1))}}} = .0303 
{{{1/((40+1))}}} = .0244
:
Let x = amt of gas added to make the 40:1 mixture
:
Write an amt of oil equation, (amt of oil remains the same, only the % changes)
.0303(2) = .0244(2+x)
.0606 = .0488 + .0244x
.0606 - .0488 = .0244x
.0118 = .0244x
x = {{{.0118/.0244}}}
x = .4836 gal of gas to be added