In the kitchen 2

In a kitchen measuring three by two meters, we want to lay square tiles with sides of 20 cm on the floor. If there are exactly 40 tiles in one package, how many such packages do we need to buy to cover the entire kitchen? (We place the tiles right next to each other).

Correct answer:

n =  4

Step-by-step explanation:

$$\begin{gathered} a=3\text{m} \\ b=2\text{m} \\ x=20\text{cm}\to \text{m}=20:100\text{m}=0.2\text{m} \\ S=a\cdot b=3\cdot 2=6{\text{m}}^2 \\ {S}_1=x^2=0.2^2=\frac{1}{25}=0.04{\text{m}}^2 \\ {n}_1=S/S_1=6/0.04=150 \\ {n}_2=n_1/40=150/40=\frac{15}{4}=3\frac{3}{4}=3.75 \\ n=\lceil n_2\rceil =\lceil 3.75\rceil =4 \end{gathered}$$

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