Plot grass seed

There is a rectangular plot of land in the schoolyard on which they want to sow grass. How many kg of grass seed will they need if the plot is 125 m long and 8.5 m wide? 1 kg of grass seed is needed for 25 m².

Final Answer:

m =  42.5 kg

Step-by-step explanation:

$$\begin{gathered} a=125\text{m} \\ b=8.5\text{m} \\ \rho =1/25=\frac{1}{25}=0.04{\text{kg/m}}^2 \\ S=a\cdot b=125\cdot 8.5=\frac{2125}{2}=1062.5{\text{m}}^2 \\ m=\rho \cdot S=0.04\cdot 1062.5=42.5\text{kg} \end{gathered}$$

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