# math

If one person can do a job in 60 minutes and another per can do it in 90 minutes, how long will it take them, working together, to do the job?

1. 👍 0
2. 👎 0
3. 👁 86
1. first person does 1/60 job/min
second does 1/90 job/min

together they do
1/60 + 1/90 = 3/180 + 2/180 = 5/180 job/min

so
(5/180)t = 1 job

t = 180/5 = 36 minutes

1. 👍 0
2. 👎 0
posted by Damon

## Similar Questions

1. ### Social Studies

Which of these is not a factor in determining whether a person is counted in the unemployment rate? A. whether the person currently has a job. B. whether the person has the skills needed to find a job. C. whether the person is

asked by Anonymous on February 10, 2014
2. ### math

Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1.5 hours. How quickly can all three fill the pool together? A.12 minutes B.15 minutes C.21 minutes

asked by Johnny on July 28, 2014
3. ### math

Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1 ½ hours. How quickly can all three fill the pool together? A. 12 minutes B. 15 minutes C. 21

asked by sharon on March 19, 2009
4. ### Social studies

Which of these factors contribute to the income potential of a job? a. the education required to be successful at a job•• b. the amount of income a person wants to make at a job c. the special skills needed to do a job

asked by Kayla on May 8, 2017
5. ### human resources

Why should job analysis involve the person who is presently in the job being analyzed? A.Because managers rarely know what their team members do all day. B.Because only that person can reveal exactly how the job is done. C.Because

asked by Anonymous on May 26, 2018

which of these factors does not contribute to the income potential the education required to be successful at a job the amount of income a person wants to make at a job the special skills needed to do a job well the enjoyment a

asked by ttng on August 21, 2015
7. ### Operations Management

A job has a normal time of 12 minutes a performance rating of .80, and an allownmce factor of 20 percent of job time. The standard time for this job in minutes is: A. 11.52 b. 12 c. 14.4 d. 15

asked by Anonymous on April 18, 2010
8. ### office management

on a job description ,what is the difference between necessary skills and desirable skills a.necessary skills are those a person needs to work at a job,and desirable skills are those that a company hopes a candidate has

asked by susue on November 18, 2013
9. ### Probability

You are the owner of an auto repair service. History tells you it takes on average 45 minutes to complete a repair job. You have determined the standard deviation for a job is 6 minutes. A women comes into your shop and tells you

asked by John on August 17, 2008
10. ### statistics

You are the owner of an auto repair service. History tells you it takes on average 45 minutes to complete a repair job. You have determined the standard deviation for a job is 6 minutes. A women comes into your shop and tells you

asked by John on August 18, 2008

More Similar Questions