Gas tank

The car's tank was two-twelfths full. Dad then added gasoline, increasing the amount by five-eighths of the tank's volume. What fraction of gasoline did the car use if the tank is now 1/3 full?

Final Answer:

s =  11/24

Step-by-step explanation:

$$\begin{gathered} n=\frac{2}{12}+\frac{5}{8}=\frac{4}{24}+\frac{15}{24}=\frac{4+15}{24}=\frac{19}{24}\doteq 0.7917 \\ n-s=1/3 \\ s=n-\frac{1}{3}=\frac{19}{24}-\frac{1}{3}=\frac{19}{24}-\frac{8}{24}=\frac{19-8}{24}=\frac{11}{24}=0.4583 \end{gathered}$$

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