Question

The outboard engine on Steve's boat uses a fuel-to-oil mixture in a 50:1 ratio. If Steve puts 2.5 gallons of fuel in the tank, how many fluid ounces of oil does he need to add? Remember to use: 1 gallon = 128 fluid ounces

Answer 1

1 gallon = 128 fluid ounces
2.5 gallons = 2.5 x 128 = 320 fluid ounces

Steve's boat uses 50 fluid ounce of fuel to 1 fluid ounce of oil, thus
for 320 fluid ounce of fuel it will use 320/50 = 6.4 fluid ounce of oil.