Full question in description. Story problem with fractions

Question

Before filling up, the car's fuel gague read one-eighth full. After fifteen gallons of gas were added, it now shows that the tank is three-fourths full. How many more gallons will it take to fill up the cars tank?

Answer 1

We are given that the tank was 1/8 full, then 15g were added, which filled the tank to 3/4 capacity.

 

Then, 3/4 - 1/8 = 15g,

which becomes 6/8 - 1/8 = 15g,

so 5/8 = 15g,

which becomes 5 = 15g • 8

solving, a full tank holds 24g

 

Then 1/8 of a full tank is 3g

 

The additional amount needed is 24g - 15g - 3g = 6g