Question 200721: I Want to know how do i find and use the method to solve this?: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! If Sally can paint a house in 4 hours, and John can paint the same house in 6
hour, how long will it take for both of them to paint the house together?
:
Here is an easy method to solve these "shared work" problems
:
Let t = time required when they work together
:
Let the completed job = 1
:
Each will do fraction of the job, the fractions will add up to 1
; + = 1
Multiply by 12 to get rid of the denominators
12* + 12* = 12(1)
Cancel the denominators, results:
3t + 2t = 12
:
5t = 12
t =
t = 2.4 hrs working together
;
;
Check solution in original equation + =
.6 + .4 = 1
;
:
Did that make sense to you?
