Question

How much 72-octane gas and 84-octane gas should be blended to make 12 gallons of 78-octane​ gas?

The amount of 72 octane gas is enter your response here gallons.
The amount of 84 octane gas is enter your response here gallons.

Answer 1

6 gallons 72-octane

6 gallons 84-octane

Explanation:

(84 + 72)/2 = 78

The average octane in 72-octane and 84-octane is 78-octane.

Therefore, you need equal amounts of each.

Answer:

6 gallons 72-octane

6 gallons 84-octane