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40 votes
One custodian cleans a suite of offices in 8 hours. When a second worker is asked to join the regular custodian, the job takes only 4 hours. How long does it take thesecond worker to do the same job alone?The second worker can do the same job alone in___hours.

User Erald Karakashi
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1 Answer

12 votes
12 votes

Given:

One custodian cleans a suite of offices in 8 hours.

So, the rate of the custodian to clean the office = 1/8

When a second worker is asked to join the regular custodian, the job takes only 4 hours.

So, the rate of both custodians = 1/4

Let the rate of the second custodian = x

So,


(1)/(8)+x=(1)/(4)

Solve for x:


x=(1)/(4)-(1)/(8)=(1)/(8)

So, the rate of the second custodian = 1/8

This means he will take 8 hours to clean the office alone

So, the answer will be:

The second worker can do the same job alone in 8 hours.

User OnkarK
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3.1k points
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