Meeting 46963

A single person would paint a fence in 6 hours with a roller. How long would it take him to paint the wall with a brush if you know that two people, one with a meeting and the other with a roller, were done in 5 hours?

Correct answer:

t₂ =  30 h

Step-by-step explanation:

$$\begin{gathered} t_1=6\text{h} \\ t=5\text{h} \\ t\cdot (1/t_1+1/t_2)=1 \\ t\cdot (t_2/t_1+1)=t_2 \\ 5\cdot (t_2/6+1)=t_2 \\ {t}_2=30 \\ {t}_2=\frac{30}{1}=30 \\ {t}_2=30=30\text{h} \end{gathered}$$

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