One gas

One gas tank was 2/3 full. The second tank of equal size was 1/5 full. The amount of gas in the 1st tank was 100 liters. How many liters is the amount of gas in the second tank?

Correct answer:

V₂ =  30 l

Step-by-step explanation:

$$\begin{gathered} V_1=100\text{l} \\ {V}_1=\frac{2}{3}\cdot V_0 \\ {V}_0=\frac{3}{2}\cdot V_1=\frac{3}{2}\cdot 100=\frac{3\cdot 100}{2}=\frac{300}{2}=150\text{l} \\ {V}_2=\frac{1}{5}\cdot V_0=\frac{1}{5}\cdot 150=\frac{1\cdot 150}{5}=\frac{150}{5}=30\text{l} \end{gathered}$$

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