statistics
posted by tony .
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.

Z = (scoremean)/SEm
SEm = SD/√n
Use same table indicated in previous post.
Respond to this Question
Similar Questions

statistics
The average age of statistics students nationwide is 22. The standard deviation is 2.5 years. Assume the age is a normally distributed variable. Find the probability that one student selected at random is older than 23. Find the probability … 
Statistics
The average age of chemical engineers is 37 years with a standard deviation of 4 years. If an engineering firm employs 25 chemical engineers, find the probability that the average age of the group is greater than 38.2 years old. If … 
statistics
The average age of a vehicle registered in the U.S. is 8 years, or 96 months. If a random sample of 36 vehicles is selected, find the probability that the mean of their age is between 98 and 100 months. Assume the standard deviation … 
statistics
The average age of a child in kindergarden is 5 years or 60 months. The standard deviation is 12 months. If a random child is selected, find the probability that the childs age is between 54 and 66 months. 
Statistics
Shown below are the data giving the length of life of lights in an underground tunnel. 9.0 months 7.0 months 8.2 months 8.3 months 7.8 months 8.1 months 7.5 months 7.6 months 9.1 months 7.4 months I calculated the standard deviation … 
Statistics
The average age of vehicles registered in the united states is 96 months, with a standard deviation of 16 months. If a random sample of 36 vehicles is selected, find the probability that the mean of their ages is between 90 and 100 … 
stats
2. The average age of a child in kindergarten is 66 months. The standard deviation is 4 months. If a random child is selected, find the probability that the mean age is: a) Between 64 and 68 months b) Greater than 62 months 
Statistics
An April 15, 2002 report in Time Magazine stated that the average age for women to marry in the United States is now 24.5 years of age. If the standard deviation is assumed to be 4.1 years, find the probability that a random sample … 
stat.
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 … 
Stats.
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 …