Francesca and Irvin are painting the walls of their clubhouse. Working alone Francesca can paint the walls in 6 hours. Irvin can complete the same walls in 4 hours if working alone. How long will it take them, working together, to finish painting. Round your answer to the nearest hundredth is necessary.

Step-by-step explanation:

Work finished by Francesca  in one hour = 1/6

Work finished by Irvin in one hour = 1/4

Work finished by Francesca and Irvin in one hour = 1/6 +1/4

5/12 of the work is completed by both in an hour

Whole work will be completed in 1*12/5 =12/5 hours = 2 2/5 hours

                                                  = 2 hours 24 minutes

a.

step-by-step explanation:

step 1 distribute 2 to every term in the parentheses

step 2 add 10 on both sides of the equal sign