How many

How many cans of blue paint need to be bought if the interior of the garden pool, which is 5 m long, 3 m wide and 1 m deep, is to be painted? There is 1 kg of paint in each can. One can is enough for 8 m² of area.

Correct answer:

n =  4

Step-by-step explanation:

$$\begin{gathered} a=5\text{m} \\ b=3\text{m} \\ c=1\text{m} \\ {S}_1=8{\text{m}}^2 \\ o=2\cdot a+2\cdot b=2\cdot 5+2\cdot 3=16\text{m} \\ S=a\cdot b+c\cdot o=5\cdot 3+1\cdot 16=31{\text{m}}^2 \\ {n}_1=S/S_1=31/8=\frac{31}{8}=3\frac{7}{8}=3.875 \\ n=\lceil n_1\rceil =\lceil 3.875\rceil =4 \end{gathered}$$

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