Question

How many gallons of fuel costing 3.35 per gallon must be mixed with 20 gallons of fuel costing 3.85 per callonm to be obtain misrure costing 3.55?

Answer 1

30 gallons of fuel costing 3.35 per gallon must be mixed.

Step-by-step explanation

Suppose,
`x` gallons of fuel costing 3.35 per gallon must be mixed with 20 gallons of another fuel costing 3.85 per gallon.

So, the total amount of the mixture
`=(x+20) gallons` and the cost of the mixture is 3.55 per gallon.

So, the equation will be....

`3.35x+(3.85*20)=3.55(x+20)\\ \\ 3.35x+77=3.55x+71\\ \\ 3.35x-3.55x=71-77\\ \\ -0.20x=-6\\ \\ x= (-6)/(-0.20)=30`

So, 30 gallons of fuel costing 3.35 per gallon must be mixed.