if gas is $4.20 a liter, how much will it cost to fill a 14-gallon tank?

Question

conversion factor:

$4.20L 1.06qt 1gal
______x________x______

1 1L 4qt

i have no clue how to set it up. i'm confused.

<font color=blue>nevermind about the problem. good night.</font>

You want to convert 14 gallons to liters. You have the conversion factors
1.06 qt = 1 L
4 qts = 1 gallon
Now, note how the factors cancel. We want to arrange them so that the units we don't want cancel while we keep the units we want. We don't want qts and gallons. We want L.

14 galx(4 qts/1 gal)x(1.06L/1qt)=??L
notice the first set of parentheses cancels gallon and converts the 14 gallons to quarts. The second set of parentheses converts the quarts to liters since quarts cancel but L does not cancel. So the answer, whatever it is, is now in liters. Multiply that by $4.20/liter, and AGAIN, note the units cancel to give dollars.
$4.20/L x (?? L from above) = ??$ since the L cancels leaving $.