Table paper coverage

The table has the shape of a rectangle with dimensions of 80 × 100 cm. Ten identical sheets of paper measuring 20 x 30 cm lie next to each other on it. Papers do not overlap or extend beyond the surface of the table. What part of the table surface is covered with paper?

Final Answer:

r =  3/4

Step-by-step explanation:

$$\begin{gathered} a=80\text{cm} \\ b=100\text{cm} \\ n=10 \\ x=20\text{cm} \\ y=30\text{cm} \\ {S}_1=a\cdot b=80\cdot 100=8000{\text{cm}}^2 \\ {S}_2=n\cdot x\cdot y=10\cdot 20\cdot 30=6000{\text{cm}}^2 \\ r=\frac{S_2}{S_1}=\frac{6000}{8000}=\frac{3}{4}=0.75 \end{gathered}$$

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