He drives each vehicle 150 miles because 450 / 3 = <<450/3=150>>150
The first car will need 3 gallons of gas because 150 / 50 = <<150/50=3>>3
The second car will need 15 gallons of gas because 150 / 10 = <<150/10=15>>15
The third car will need 10 gallons of gas because 150 / 15 = <<150/15=10>>10
He will need 28 gallons in total because 3 + 15 + 10 = <<3+15+10=28>>28
This will cost him $56 because 28 x $2 = $<<28*2=56>>56
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