# Question: The average age for licensed drivers in the county is

The average age for licensed drivers in the county is µ = 40.3 years with a standard deviation of σ = 13.2 years.

a. A researcher obtained a random sample of n = 16 parking tickets and computed an average age of

M = 38.9 years for the drivers. Compute the z-score for the sample mean and find the probability of obtaining an average age this young or younger for a random sample of licensed drivers. Is it reasonable to conclude that this set of n = 16 people is a representative sample of licensed drivers?

b. The same researcher obtained a random sample of n = 36 speeding tickets and computed an average age of µ = 36.2 years for the drivers. Compute the z-score for the sample mean and find the probability of obtaining an average age this young or younger for a random sample of licensed drivers. Is it reasonable to conclude that this set of n = 36 people is a representative sample of licensed drivers?

a. A researcher obtained a random sample of n = 16 parking tickets and computed an average age of

M = 38.9 years for the drivers. Compute the z-score for the sample mean and find the probability of obtaining an average age this young or younger for a random sample of licensed drivers. Is it reasonable to conclude that this set of n = 16 people is a representative sample of licensed drivers?

b. The same researcher obtained a random sample of n = 36 speeding tickets and computed an average age of µ = 36.2 years for the drivers. Compute the z-score for the sample mean and find the probability of obtaining an average age this young or younger for a random sample of licensed drivers. Is it reasonable to conclude that this set of n = 36 people is a representative sample of licensed drivers?

**View Solution:**## Answer to relevant Questions

Callahan (2009) conducted a study to evaluate the effectiveness of physical exercise programs for individuals with chronic arthritis. Participants with doctor-diagnosed arthritis either received a Tai Chi course immediately ...For a population with σ = 12, how large a sample is necessary to have a standard error that is: a. less than 4 points? b. less than 3 points? c. less than 2 point? Researchers at a National Weather Center in the northeastern United States recorded the number of 90° days each year since records first started in 1875. The numbers form a normal shaped distribution with a mean of µ = 9.6 ...A researcher is evaluating the influence of a treatment using a sample selected from a normally distributed population with a mean of µ = 80 and a standard deviation of s = 20. The researcher expects a 12-point treatment ...To evaluate the effect of a treatment, a sample of n = 8 is obtained from a population with a mean of µ = 40, and the treatment is administered to the individuals in the sample. After treatment, the sample mean is found to ...Post your question