Hall

The rectangular hall will have to pave with square tiles with a side length of 15 cm. The hall has a length of 18 meters and a width of 3 m. How many tiles need to buy if 2 percent of the amount is disrupted during the work?

Correct answer:

n =  2448

Step-by-step explanation:

$$\begin{gathered} a=15\text{cm}\to \text{m}=15:100\text{m}=0.15\text{m} \\ x=18\text{m} \\ y=3\text{m} \\ {n}_1=\lceil x/a\rceil =\lceil 18/0.15\rceil =120 \\ {n}_2=\lceil y/a\rceil =\lceil 3/0.15\rceil =20 \\ {S}_1=n_1\cdot n_2=120\cdot 20=2400 \\ q=100\%+2\%=1+\frac{2}{100}=1.02 \\ n=q\cdot S_1=1.02\cdot 2400=2448 \end{gathered}$$

Try another example