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Deandre can paint a small room in 6 hours. Deandre and Casey together can paint the same room in 4 hours. How long would it take for Casey to paint the room alone? Express your answer as a decimal. If necessary, round to the nearest tenth of hour.

User Habrewning
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1 Answer

14 votes
14 votes

Answer:

Explanation:

If D can paint the room in 6 hours, in 1 hour she gets
(1)/(6) of the room painted;

If C can paint the room in x hours, in 1 hour she gets
(1)/(x) of the room painted.

It takes 4 hours to paint it together. Setting up the classic work equation gives us


(1)/(6)+(1)/(x)=(1)/(4) and we need to solve for x. Multiply everything through by the LCM which is 12x:


12x((1)/(6)+(1)/(x)=(1)/(4)) making our equation simplify to

2x + 12 = 3x and solve for x:

12 = x

C can paint the room alone in 12 hours.

User OldUgly
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