Question 232515
If Sally can paint a house in 4 hours, and John can paint the same house in 6 hours, how long will it take for both of them to paint the house together?
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S paints 1/4 house per hour.
J paints 1/6 per hour.
Together, they paint 1/4 + 1/6 per hour = 5/12 per hour.
--> 12/5 hours/house
= 2.4 hours