Volume - pool

The pool, 10.5 m wide, 50 m long, and 3 m deep, will be filled in 3 days. On the first day, 2/5 of the water volume flowed into it, and 1/3 of the rest on the second day. How many liters of water flowed into the pool on the third day?

Correct answer:

V =  630000 l

Step-by-step explanation:

$$\begin{gathered} a=10.5\text{m} \\ b=50\text{m} \\ c=3\text{m} \\ {V}_1=a\cdot b\cdot c=10.5\cdot 50\cdot 3=1575{\text{m}}^3 \\ {f}_1=1-\frac{2}{5}=\frac{1\cdot 5}{5}-\frac{2}{5}=\frac{5}{5}-\frac{2}{5}=\frac{5-2}{5}=\frac{3}{5}=0.6 \\ {f}_2=f_1-\frac{f_1}{3}=\frac{3}{5}-\frac{\frac{3}{5}}{3}=\frac{2}{5}=0.4 \\ {V}_2=f_2\cdot V_1=\frac{2}{5}\cdot 1575=\frac{2\cdot 1575}{5}=\frac{3150}{5}=630{\text{m}}^3 \\ V=V_2\to \text{l}=V_2\cdot 1000\text{l}=630\cdot 1000\text{l}=630000\text{l}=630000\text{l} \end{gathered}$$

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