Problema Solution
Three secretaries worked together typing a group of form letters. Jones could have done them alone in 2h, Brown in 3h, and Smith in 2h. How long did the secretaries need to type the letters working together?
Answer provided by our tutors
let 'x' represent the time it took them working together, then:
1/x = 1/2 + 1/3 + 1/2
solving for 'x' we have x=0.75
0.75 hours * 60 minutes/hour = 45 minutes
it will take them 45 minutes, working together