Temporary 67594

Two temporary workers comb apples from 15 apple trees in 5 hours and 20 minutes. After two hours, three other temporary workers came to help them. How long did it take to comb apples from these 15 trees?

Result

x = 3:20 h

Step-by-step explanation:

$$\begin{gathered} t_1=5:20=5hr20min=5+\frac{20}{60}=5.3333hr\doteq 5.3333 \\ {t}_2=2\text{h} \\ 2\cdot t_1=2\cdot t_2+(2+3)\cdot (x-t_2) \\ 2\cdot 5.3333333333333=2\cdot 2+(2+3)\cdot (x-2) \\ 5x=16.666667 \\ x=\frac{16.66666667}{5}=3.33333333 \\ x=\frac{10}{3}\doteq 3.333333=3.33333=3:20\text{h} \end{gathered}$$

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