SOLUTION: Twins Dante's and Edmund have been taking turns each week shampooing the living room carpet (dimensions 5.40m north-south by 3.60m east west) it takes Dante three hours to shampoo

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Twins Dante's and Edmund have been taking turns each week shampooing the living room carpet (dimensions 5.40m north-south by 3.60m east west) it takes Dante three hours to shampoo       Log On


   



Question 908726: Twins Dante's and Edmund have been taking turns each week shampooing the living room carpet (dimensions 5.40m north-south by 3.60m east west) it takes Dante three hours to shampoo the whole carpet, while Edmund can do the same job in two and a half hours. how long does it takes them to shampoo the whole carpet?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
it takes Dante three hours to shampoo the whole carpet, while Edmund can do the same job in two and a half hours.
how long does it takes them to shampoo the whole carpet?
:
let t = time required when they work together to shampoo the whole carpet
let the completed job = 1 (a clean carpet
:
Each will do a fraction of the carpet, the two fractions add up to 1
t%2F3 + t%2F2.5 = 1
multiply by 15 to clear the denominators
15*t%2F3 + 15*t%2F2.5 = 15*1
Cancel the denominators and you have
5t + 6t = 15
t = 15/11
t = 1.36 hrs or 1 + .36(60) = 1 hr 22 min working together
:
;
The size of the carpet is not relevant to this problem