Question 509134
If Sally can paint a house in 4 hours, & 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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Let x = time (hours) it takes for both
then
x(1/4 + 1/6) = 1
multiplying both sides by 12:
x(3 + 2) = 12
x(5) = 12
x = 12/5 hours
x = 2.4 hours
or
x = 2 hours and 24 minutes