On the plot 2

On a rectangular plot there will be a forest nursery. One side of the plot measures 12 m, the other 3 m more.

a) how many metres of fencing will be needed to fence the forest nursery?
b) how many seedlings will they plant if their mutual distance is 1 m and also 1 m from the fence?
c) the price of a post for fencing is 7€ and 1 m of fencing costs 3€. how much will the fencing of the nursery cost if the distance between posts is 3 m?

Final Answer:

o =  54 m
n =  154
x =  288 Eur

Step-by-step explanation:

$$\begin{gathered} a=12\text{m} \\ b=a+3=12+3=15\text{m} \\ o=2\cdot (a+b)=2\cdot (12+15)=54\text{m} \end{gathered}$$

$$\begin{gathered} d=1\text{m} \\ {S}_1=(a-d)\cdot (b-d)=(12-1)\cdot (15-1)=154{\text{m}}^2 \\ {S}_2=d^2=1^2=1{\text{m}}^2 \\ n=S_1/S_2=154/1=154 \end{gathered}$$

$$\begin{gathered} s=o/3=54/3=18 \\ x=7\cdot s+3\cdot o=7\cdot 18+3\cdot 54=288\text{Eur} \end{gathered}$$

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