Bathroom 3

De Mesa family will soon be occupying their newly renovated house. However, the bathroom, measuring 10ft by 16ft, is still covered with tiles. If the tiles they desire measure 2/5 ft by 2/5ft, how many tiles will they need to cover the bathroom floor?

Correct answer:

n =  1000

Step-by-step explanation:

$$\begin{gathered} a=10\text{ft} \\ b=16\text{ft} \\ x=\frac{2}{5}=0.4\text{ft} \\ {n}_1=a/x=10/\frac{2}{5}=10:\frac{2}{5}=10\cdot \frac{5}{2}=\frac{10\cdot 5}{2}=\frac{50}{2}=25 \\ {n}_2=b/x=16/\frac{2}{5}=16:\frac{2}{5}=16\cdot \frac{5}{2}=\frac{16\cdot 5}{2}=\frac{80}{2}=40 \\ n=n_1\cdot n_2=25\cdot 40=1000 \end{gathered}$$

Try another example