Initially, 1/4 of the tank was filled.
After adding 12 gallons, it was 3/4 full.
Increase in fuel filled portion =
[tex] \frac{3}{4} - \frac{1}{4} = \frac{3 - 1}{4} = \frac{2}{4} \\ [/tex]
So 2/4 of the tank = 12 gallons
1/4 of tank = 12 ÷ 2 = 6 gallons
4/4 of tank = 6×4 = 24 gallons
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Portion remaining to be filled =
[tex]1 - \frac{3}{4} = \frac{4 - 3}{4} = \frac{1}{4} \\ [/tex]
Fuel needed = 1/4 × 24 = 6 gallons
So you need 6 more gallons to fill the tank
