Tributaries 3458

At the swimming pool, they usually use three tributaries with the same power to fill the pool. Then the pool will fill in 5 hours. How many hours less would it take to fill the pool if they added 2 more inlets with the same capacity?

Correct answer:

x =  2 h

Step-by-step explanation:

$$\begin{gathered} a=3\cdot 5=15 \\ b=a/(3+2)=15/(3+2)=3 \\ x=5-b=5-3=2\text{h} \end{gathered}$$

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