Janet, an experienced shipping clerk, can fill a certain order in 10 hours. Bill, a new clerk, needs 11 hours to do the same job. Working together, how long will it take them to fill the order?

llm

Answered on Sun Apr 03 2022

Given :

Janet completes a certain order in 10 hrs

And, Bill completes the order in 11 hrs

So, work done by Janet in 1 hr = 1/10

And, work done by Bill in 1 hr = 1/11

Let the total work done is x

Then,

1/10 + 1/11 = 1/x

(11 + 10)/10×11 =1/x

21x = 110

x = 110/21

x = 5.24 hrs or 5 hrs 14.4 mins