Dusan

a) Dusan break two same window, which has triangular shape with a length of 0.8 m and corresponding height 9.5 dm. Find how many dm² of glass he needs to buy for glazing of these windows.

b) Since the money to fix Dusan has not, must go to the paint job advertising posters in the shape of a parallelogram. Its length is 4.9 m and corresponding height is 3.5 meters. How many kg of color need to purchase when 1 kg is sufficient for painting the surface of 4 m ².

c) When Dusan completed painting will return home. He want to relax in your room. How many m² has his room where the floor is made from 600 parquet tiles? Parquet floor in the room are shaped rhomboid with side 2.5 dm long and appropriate height of 0.8 dm.

Correct answer:

a =  76 dm²
b =  5 kg
c =  12 m²

Step-by-step explanation:

$$\begin{gathered} x=0.8\text{m}\to \text{dm}=0.8\cdot 10\text{dm}=8\text{dm} \\ y=9.5\text{dm} \\ a=2\cdot \frac{x\cdot y}{2}=2\cdot \frac{8\cdot 9.5}{2}=76{\text{dm}}^2 \end{gathered}$$

$b=\lceil 4.9\cdot 3.5/4\rceil =5\text{kg}$

$$\begin{gathered} n=600 \\ {x}_1=2.5\text{dm}\to \text{m}=2.5:10\text{m}=0.25\text{m} \\ {y}_1=0.8\text{dm}\to \text{m}=0.8:10\text{m}=0.08\text{m} \\ c=n\cdot x_1\cdot y_1=600\cdot 0.25\cdot 0.08=12{\text{m}}^2 \end{gathered}$$

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