Posted by **julie** on Tuesday, October 5, 2010 at 4:16pm.

A major taxi company is concerned that its proportion of late arrivals has substantially increased in the past month. Historical data shows that on the average 18% of the company taxis have arrived late. In a random sample of 1,240 taxis, 310 taxis have arrived late. If we are conducting a hypothesis test of a single proportion to determine if the proportion of late arrivals has increased: What is the value of the calculated test statistic?

- statistics -
**MathGuru**, Tuesday, October 5, 2010 at 8:24pm
Using a formula for a binomial proportion one-sample z-test with your data included, we have:

z = .25 - .18 -->test value (310/1240 = .25) minus population value (.18)

divided by

√[(.18)(.82)/1240] -->.18 is test value, .82 is 1 - .18, and 1240 is the sample size

Finish the calculation for the value of the test statistic.

- statistics -
**Anonymous**, Wednesday, February 26, 2014 at 9:13pm
6.416

## Answer This Question

## Related Questions

- Statistic - A major airline company is concerned that its proportion of late ...
- math - An airline tracks data on its flight arrivals. Over the past six months, ...
- english - Which of these is a simple sentence and why? 1) Karen and David ...
- English - Which of the following is a simple sentence? A. Karen and David ...
- English - Which of the following is a simple sentence? A. Karen and David ...
- statistics - "Separate the data by company and do descriptive stats for each. ...
- Data Analyse - Question 1 Production Rates A manufacturing company wishes to ...
- math - A teacher drove 280 miles to attend a mathematics conference and arrived ...
- Finite Math - Continental Motors manufactures taxis and airport limousines at ...
- math - Question 1 Production Rates A manufacturing company wishes to estimate ...

More Related Questions