SOLUTION: How do I figure out this question? If sally paints a house in 4 hours and sam does the same house in 6 hours, how long will it take them both to do the same house?

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Question 182369: How do I figure out this question? If sally paints a house in 4 hours and sam does the same house in 6 hours, how long will it take them both to do the same house?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If sally paints a house in 4 hours and sam does the same house in 6 hours, how long will it take them both to do the same house?
:
A typical shared work problem
:
let t = time required when they work together
Let the completed job = 1 (the painting of the house)
:
t%2F4 + t%2F6 = 1
Multiply equation by the LCM to get rid of the denominators
12*t%2F4 + 12*t%2F6 = 12(1)
Results
3t + 2t = 12
5t = 12
t = 12%2F5
t = 2.4 hrs working together or; .4 * 60 = 24 min, so 2 hrs 24 min
:
:
Check solution in original equation:
2.4%2F4 + 2.4%2F6 = 1
.6 + .4 = 1