Pears

Boris, Philip, and Martin harvested pears. It took Boris 30 minutes to harvest one full crate, 20 minutes for Philip, and 36 minutes for Martin. Calculate how long it would take them to pick up five full crates together.

Final Answer:

t =  45 min

Step-by-step explanation:

$$\begin{gathered} 5=t\cdot (\frac{1}{30}+\frac{1}{20}+\frac{1}{36}) \\ 5=t\cdot (1/30+1/20+1/36) \\ 20t=900 \\ t=\frac{900}{20}=45 \\ t=45=45\text{min} \end{gathered}$$

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