Question

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.

Answer 1

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,

$\frac{1}{8}+x=\frac{1}{4}$

Solve for x:

$x=\frac{1}{4}-\frac{1}{8}=\frac{1}{8}$

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.