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16 votes
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Rob can mop a warehouse in 10 hours. Maria can mop the same warehouse in 11 hours. Find how long it would take them if they worked together.

User Jose Llausas
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2 Answers

14 votes
14 votes
The answer would be 21 good luck hope you get it correct
User Jocki
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17 votes
17 votes

Answer:

It would take them
(110)/(21) or approximately 5.24 hours together

Explanation:

Use the algebra work formula,
(1)/(tb) =
(1)/(t1) +
(1)/(t2), where tb is the time together, t1 is the time of one person individually, and t2 is the time of the other person.

Plug in 10 and 11:


(1)/(tb) =
(1)/(t1) +
(1)/(t2)


(1)/(tb) =
(1)/(10) +
(1)/(11)

Find the common denominator, then add the fractions together:


(1)/(tb) =
(11)/(110) +
(10)/(110)


(1)/(tb) =
(21)/(110)

Cross multiply and solve for tb:

110 = 21tb

5.24 = tb

So, it would take them
(110)/(21) or approximately 5.24 hours together

User Mattias Farnemyhr
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2.9k points