statistics
posted by Josh .
The diameter of small Nerf balls manufactured at a factory in China is expected to be approximately normally distributed with a mean of 5.2 inches and a standard deviation of .08 inch. Suppose a random sample of 20 balls is selected. Find the interval that contains 87% of the sample means.

87% = mean ± 1.51 SEm
SEm = SD/√n 
What is square root n?

The diameter of small Nerf balls manufactured at a factory in China is expected to be approximately normally distributed with a mean of 5.2 inches and a standard deviation of .08 inch. Suppose a random sample of 20 balls is selected. Find the interval that contains 87% of the sample means
Respond to this Question
Similar Questions

statistics
The heights of 10000 individuals are approximately normally distributed with a mean of 70 inches and a standard deviation of 3 inches. Find the probability that a person picked at random from this group will be between 65 and 74 inches … 
statistics
Assume that the population of heights of male college students is approximately normally distributed with mean m of 70.63 inches and standard deviation s of 6.47 inches. A random sample of 88 heights is obtained. Show all work. (A) … 
statistics
The diameters of apples in a certain orchard are normally distributed with a mean of 4.77 inches and a standard deviation of 0.43 inches. Show all work. (A) What percentage of the apples in this orchard is larger than 4.71 inches? 
statistics
The diameters of apples in a certain orchard are normally distributed with a mean of 4.77 inches and a standard deviation of 0.43 inches. Show all work. (A) What percentage of the apples in this orchard is larger than 4.71 inches? 
statistics
Help me! Population of heights of college students is approximately normally distributed with a mean of 64.37 inches and standard deviation of 6.26 inches A random sample of 74 heights is obtained. Find the mean and standard error … 
statistics
It is known that for a certain firm specializing in manufacturing female Tshirts, the ‘Small’ sizes have a shoulder size of 14 inches or less. If these Tshirt shoulder sizes are normally distributed with a mean of 16 inches and … 
Statistics
The inside diameter of the automobile wheel bearing sets at a factory is expected to be normally distributed with a mean of 1.30inches and a standard deviation of 0.04 inches. What is the probability that a randomly selected wheel … 
math
The diameters of pencils produced by a certain machine are normally distributed with a mean of 0.30 inches and a standard deviation of 0.01 inches. In a random sample of 460 pencils, approximately how many would you expect to have … 
Statistics
Tennis Ball Manufacturing: A company manufactures tennis balls. When its tennis balls are dropped onto a concrete surface from a height of 100 inches, the company wants the mean height of a ball’s bounce upward to be 55.5 inches. … 
Statistics Please help me :(
I have no idea where to even start. Suppose heights of men are normally distributed with a mean 69.0 inches and standard deviation 2.8 inches. How many of a group of 1000 men would you expect to be between 70 and 72 inches tall?