65/25
800 miles / 16 miles per gallon = 50 gallons x $4 per gallon = $200.
1,200 miles at 12 miles per gallon = 100 gallons.100 gallons at $3.50 per gallon = $350 .
$121.76
256
72.64
$750.
(1,000 miles) x (1 gallon/20 miles) x ($4/gallon) = $4,000/20 = $200
334/15 assuming miles/gallon (miles per gallon) is constant
50.54
$211.20
$129.
$533.33