Garden digging

Pavel dug in the morning, 1/5 of the garden in the afternoon, and then 1/2 of the unoccupied part. What part of the garden remained unopened?

Final Answer:

x =  2/5

Step-by-step explanation:

$$\begin{gathered} a=1-\frac{1}{5}=\frac{1\cdot 5}{5}-\frac{1}{5}=\frac{5}{5}-\frac{1}{5}=\frac{5-1}{5}=\frac{4}{5}=0.8 \\ x=a-\frac{1}{2}\cdot a=\frac{4}{5}-\frac{1}{2}\cdot \frac{4}{5}=\frac{2}{5}=0.4 \end{gathered}$$

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