Garden

The rectangular garden is 72 m long and 25 m wide. Calculate by how much m² its area will be reduced if it is surrounded by an ornamental fence 50 cm wide.

Correct answer:

S =  109.44 m²

Step-by-step explanation:

$$\begin{gathered} a=99\text{m} \\ b=84\text{m} \\ h=30\text{cm}\to \text{m}=30:100\text{m}=0.3\text{m} \\ {S}_1=a\cdot b=99\cdot 84=8316{\text{m}}^2 \\ {S}_2=(a-2\cdot h)\cdot (b-2\cdot h)=(99-2\cdot 0.3)\cdot (84-2\cdot 0.3)=8206.56{\text{m}}^2 \\ S=S_1-S_2=8316-8206.56=109.44{\text{m}}^2 \end{gathered}$$

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