Business statistics-normal distribution curves

Reference no: EM1391823

Assume that we will randomly select a sample of 64 measurements from a population having a mean equal to 20 and a standard deviation equal to 4.

a. Describe the shape of the sampling distribution of the sample mean x. Do we need to make any assumptions about the shape of the population? Why or why not?

b. Find the mean and the standard deviation of the sampling distribution of the sample mean.

c. Calculate the probability that we will obtain a sample mean greater than 21; that is, calculate P(x-bar > 21). Hint: find the z value corresponding to 21 by using mean and standard deviation because we wish to calculate a probability about x-bar. Then sketch the sampling distribution and the probability.

d. Calculate the probability that we will obtain a sample mean less than 19.385; that is, calculate P(x-bar < 19.385).

Reference no: EM1391823

Questions Cloud

Explain two sensory changes : Explain two sensory changes that coincide with the emergence of diurnality among primates. Discuss specific brain regions or sensory organs if applicable.

Reasons of developing frequency distribution : Critically discuss the purpose of developing a frequency distribution? What is the relationship between the relative frequency and the cumulative frequency? Could a frequency distribution contain qualitative data? Why?

Injections of tc cells : Injections of TC cells completely removed all Hepatitis B viruses from infected mice, but the injections killed only 5 percent of the infected liver cells.

Weights of water taxi passengers : When water taxi sank in the Baltimore Inner Harbor, an investigation revealed that the safe passenger load for water taxi was 3500 lbs. It was also noted that the mean weight of passenger was assumed to be 140 lbs.

Business statistics-normal distribution curves : Assume that we will randomly select a sample of 64 measurements from a population having a mean equal to 20 and a standard deviation equal to 4.

Severity of a disease in a family : Explain how incomplete penetrance, variable expressivity, pleiotropy, and genetic heterogeneity can affect the severity of a disease in a family.

Question on risk analysis : In performing the symmetric approximation, you calculate a mean of the total system cost as $1,725K. The variance is 22500. The POE is $1,600K.

Determining accurate measurement of the frequency : Because you want to see if you can determine a more accurate analysis of the frequency of the disease allele in your population, your sample 2,000 individuals

Calculate the frequency of the normal allele : Assume you are a population geneticist, studying a particular disease which is inherited as an autosomal recessive trait. In the population you are studying, the incidence of the disease is three percent.

User Account

All Pages