Math Central - mathcentral.uregina.ca
Quandaries & Queries
Q & Q
. .
topic card  



list of
. .
start over

11 items are filed under this topic.
Ten workers perform one job in five days 2007-08-21
From Kenneth:
If ten workers perform one job in 5 days, one person performs one job in how many days?

Here is the calculation that I used:
(10 workers X 1 job X 5 days)/(1 person X 1 job X ? days)

The above equals 50/1, and the answer is 50 days because 50/1 = 50. In this calculation I can determine any number of workers or days if the number of jobs remains the same as that in the group of factors from the numerator (10 workers X 1 job X 5 days), that is 1 job. Here is another example to help clarify: (10 workers X 1 job X 5 days)/(? workers X 1 job X 10 days) This equals 50/10. The answer is 5 workers. So, if 10 workers can perform 1 job in 5 days, 5 workers can perform 1 job in 10 days.

Now, if I replace "1 job" from (10 workers X 1 job X 5 days) with a different number, for example, 4 jobs, this amount will prevent the calculation from producing the correct answer.

Here is an example: (10 workers X 1 job X 5 days)/(10 workers X 4 jobs X ? days) Mathematically, the calculation works, but the answer, 1.25 days, is not correct, if I'm not mistaken. If 10 workers can perform 1 job in 5 days, they cannot, by working at the same rate, perform 4 jobs in 1.25 days.

Can you explain, with a simple explanation, why the number representing the jobs in this calculation needs to be the same in the group of factors in both the numerator and in the denominator in order to provide the correct answer?

Answered by Harley Weston.
Worker A can do a piece of work in 15 days,... 2006-03-23
From Kenneth:
Worker A can do a piece of work in 15 days, worker B in 12 days, and worker C in 10 days. Worker A works 2 days, worker B 3 days, and worker C 3 days. In what time can worker A and worker B finish the job by working together?
Answered by Penny Nom.
Real Pay 2005-11-07
From Judy:
Is there a formula for computing "real pay"? Example - you are offered a position in your home town for $A, and another position in another town for $B. To work at $B job there would be so many hours in commute time involved (z), and a real daily commute cost (either train, bus, or auto mileage-wear, etc.) (x). How would you calculate the real pay of job $B in relation to job $A?
Answered by Claude Tardif.
Jobs relating to the topics of ratios and proportions 2005-05-17
From Alexa:
What are some jobs relating to the topics of ratios and proportions other than architects and map makers?
Answered by Walter Whiteley.
Math jobs 2003-12-12
From Veronica:
Do you know a couple of jobs I can get when I am older in Math?
Answered by Harley Weston.
Motivators 2001-01-16
From Michelle Stapley:
Do you know of any (or where I can find) student motivators for math at the secondary level? Basically any way I can motivate my students to WANT to learn math.
Answered by Penny Nom.
Estimating the time to complete a job 2000-12-03
From Jack Hook:
I'm a contractor and need to estimate how much time it will take me to do a specific job. A previous job I did was 6,480.16 Square Feet and I was able to paint it in 31.5 hours. In estimating my next job, how many hours will it take me to paint 11,000 Sqare Feet.
Answered by Penny Nom.
Math in various careers 2000-04-18
From Jennifer Jones:
I am a Fifth grade student researching how math is used in various careers. What kind of math is used in your career? How do you use math?
Answered by Harley Weston.
Job outlook 2000-04-12
From Shelby Faust:
what is the future demand, in numbers, of a secondary mathematics teacher? what are the projected costs for this career? what technology skills will be needed for this career?
Answered by Walter Whiteley.
Careers after a math degree 2000-03-31
From Jeanne Hyer:
What type of careers can a person have with a math degree, and what is the closest thing that you have to an undergraduate degree in financial mathematics? (Administration, math, actuarial science, etc.)
Answered by Harley Weston.
Work jobs 1999-04-19
From Cindy Miller:
Hi. I'm a college student, majoring in Elementary Education. This semester I am taking a math class for elementary school teachers.

I'm not sure if you can help out, but here is what I need. For the class, I am supposed to make 10 work jobs for students. Simple things that teach math that students can work on individually, for example after finishing a test.

If you have any suggestions, I would really appreciate it.
Answered by Penny Nom.




Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.



Home Resource Room Home Resource Room Quandaries and Queries Mathematics with a Human Face About Math Central Problem of the Month Math Beyond School Outreach Activities Teacher's Bulletin Board Canadian Mathematical Society University of Regina PIMS