Can anyone help me step by step with this word problem: The fuel for a certain two cycle engine is a mixture of 8 parts gasoline and 2 parts oil. How many gallons of gasoline are needed to make 20 gallons of fuel?

Question

anonymous · Answer

If it was 10 gallon fuel, we would have 8 gallon gas and 2 gallon oil. Since we want 20 gallon, multiply everything by 2
8 gallon gas   + 2 gallon oil=10
16 gallon gas +4 gallon oil= 20 gallon fuel

anonymous · Answer

That makes sense to me, but the answer for this question in my book was given as 16. ?

anonymous · Answer

it is 16

anonymous · Answer

Ohhhh I am sorry I read that wrong  for some reason I thought 20 was the answer.

anonymous · Answer

$$\underline{16\space gallon\space gas} +4\space gallon\space oil= 20 gallon fuel$$

anonymous · Answer

Thank You so much :)