## quantitative methods: random sample to meas. oil changes

Simplificatation, evaluation, linear equations, linear graphs, linear inequalities, basic word problems, etc.
dianharper
Posts: 2
Joined: Sun Jan 18, 2009 10:01 pm
Contact:

### quantitative methods: random sample to meas. oil changes

In a small town of about 1200 people you have taken a random sample of 100 people. These 100 represent the total 1200 people. You are trying too ascertain the number of oil changes; so that, you can decide whether to open a Fast Lube location. The following table provides the results.

Code: Select all

``` Number of Weeks between respondents oil changes 30 8 40 10 20 12```
Anyone not responding is assumed to never change his/her oil. For each group how many oil changes are made per week. Provide this information in the next table.

Code: Select all

``` Number of Average Oil changes per Total oil respondents week per respondent changes 30 40 20 ```
a) What are the total oil changes per week for these 100 people?

b) What are the total oil changes per week for the 1200 people in this town.

c) If an oil change is \$30 how much will the town spend on oil changes per week?

d) Could you make a profit on a Quick Lube in this small town? Why? Why not?

stapel_eliz
Posts: 1628
Joined: Mon Dec 08, 2008 4:22 pm
Contact:
To fill in the second table, divide to find the "fractional" oil change done "per week". For instance, if I get my oil changed every two weeks, then I get "half" an oil change "per week". If I get "half" an oil change and my neighbor gets "one-third" of an oil change, then the two of us together get 1/2 + 1/3 = 5/6 of an oil change per week.
a) What are the total oil changes per week for these 100 people?