A car 6

A car holds 15 liters of fuel. The car consumes 3 liters of fuel each 100 km. We started a trip of 350 km with a full tank of fuel. How much fuel remains in the tank at the end of the trip?

Correct answer:

V₂ =  4.5 l

Step-by-step explanation:

$$\begin{gathered} V=15\text{l} \\ {V}_1=\frac{350}{100}\cdot 3=\frac{350\cdot 3}{100}=\frac{1050}{100}=\frac{21}{2}=10.5\text{l} \\ {V}_2=V-V_1=15-\frac{21}{2}=\frac{15\cdot 2}{2}-\frac{21}{2}=\frac{30}{2}-\frac{21}{2}=\frac{30-21}{2}=\frac{9}{2}=\frac{9}{2}\text{l}=4.5\text{l} \end{gathered}$$

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