Homework Help: stat.

Posted by chris on Sunday, March 17, 2013 at 5:36pm.

The average age of a vehicle registered in the United States is 8 years, or 96 months. Assume the standard deviation is 16 months. If a random sample of a group of 48 vehicles is selected find the probability that the mean of the group’s age is between 90 and 100 months.

stat. - PsyDAG, Monday, March 18, 2013 at 12:40pm
Z = (score-mean)/SEm

SEm = SD/√n

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z scores.

This is a distribution of means, while your next post is a distribution of raw scores.

Answer this Question

Related Questions

statistics - The average age of a vehicle registered in the U.S. is 8 years, or ...
Statistics - The average age of vehicles registered in the united states is 96 ...
statistics - The average age of a child in kindergarden is 5 years or 60 months...
stats - 2. The average age of a child in kindergarten is 66 months. The standard...
science - Shown below are the data giving the length of life of lights in an ...
Statistics - Shown below are the data giving the length of life of lights in an ...
Statistics - . A certain company makes 12-volt car batteries. After many years ...
Statistics - An April 15, 2002 report in Time Magazine stated that the average ...
tempe - An April 15, 2002 report in Time Magazine stated that the average age ...
Statistics - A certain company makes 12-volt car batteries. After many years of ...

For Further Reading

First Name:
School Subject:
Answer: