Question

Company X can install chairs in a theater in 10 hours company Y can install them in 15 hours. How long would the two companies working together need to install the chairs?

Answer 1

Answer: 6 hours

Explanation:

Given : The time taken by Company X to install chairs :
`t_1=10\text{ hours}`

The time taken by Company Y to install chairs :
`t_2=15\text{ hours}`

Then , the time taken (T) by both of them to install the chairs if they work together is given by :-

`(1)/(T)=(1)/(t_1)+(1)/(t_2)\\\\\Rightarrow\ (1)/(T)=(1)/(10)+(1)/(15)\\\\\Rightarrow(1)/(T)=(10)/(60)\\\\\Rightarrow\ T=6`

Hence, it will take 6 hours to the two companies if they working together .