<PRE><B>Question 506533</B>
One man can paint a garage in 28 hours.  After working for 12 hours, he was given a new job, and a second man finished painting in 18 hours.  How long would the second man take take to paint to whole garage?
.
Let x = time (hours) it takes second man to paint whole garage
then
12(1/28) + 18(1/x) = 1
multiplying both sides by 28x:
12(x) + 18(28) = 28x
12x + 504 = 28x
504 = 16x
31.5 hours = x

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