Approximately 81476

Approximately how many square meters of paper are needed to make a 500-page book that measures 29.7 cm by 21 cm (printed on both sides of the paper).

Correct answer:

S =  15.6 m²

Step-by-step explanation:

$$\begin{gathered} a=29.7\text{cm} \\ b=21\text{cm} \\ n=500/2=250 \\ {S}_1=a\cdot b=29.7\cdot 21=\frac{6237}{10}=623.7{\text{cm}}^2 \\ {S}_2=n\cdot S_1=250\cdot 623.7=155925{\text{cm}}^2 \\ S=S_2\to {\text{m}}^2=S_2:10000{\text{m}}^2=155925:10000{\text{m}}^2=15.6{\text{m}}^2=15.6{\text{m}}^2 \end{gathered}$$

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