Mathematics: One crew can seal a parking lot in 10 hours and another in 14 hours. how long will it take to seal the parking lot if the two crews work together?

One crew can seal a parking lot in 10 hours and

Ответ:

AlwaysMarcus5577

12.03.2022

Suppose that all work that has to be done is 1. Then:

One crew can do this work in 10 hours. This means that they will do $\dfrac{1}{10}$ per hour.Another crew can do this work in 14 hours.This means that they will do $\dfrac{1}{14}$ per hour.Both crews together will do $\dfrac{1}{10}+\dfrac{1}{14}=\dfrac{7+5}{70}=\dfrac{12}{70}=\dfrac{6}{35}$ per hour.

If together they can do $\dfrac{6}{35}$ per hour, then for all work they will spend