Statistics and Probability Answers

If the weights of 600 students are normally distributed with mean of 50 kilograms and a variance of 16kilograms.

a.) Determine the percentage of students with weights lower than 55 kgs.

b.) How many students with weight between 50kgs and 55kgs.

If the weights of 600 students are normally distributed with a mean of 50 kilograms and a variance of 16 kg

b.) How many students with weights between 50 kgs and 55 kgs. (5 points)

An insurance company found that 45% of all insurance policies are terminated before their maturity date. Assume that 10 polices are randomly selected from the company’s policy database. Assume a Binomial experiment.

a) What is the probability that eight policies are terminated before maturity?

b) What is the probability that at least eight policies are terminated before maturity?

c) What is the probability that at most eight policies are not terminated before maturity?

You are given a population of 3 elements , which are 3,4,5. Suppose all possible samples of size 2 are drawn from the population with replacement, compute for the following;

Mean of the sample means;

Variance of the sample means; and standard deviation of the sample means

A manufacturer claims that the average tensile

strength of thread A exceeds the average tensile

strength of thread B. To test this claim, 50 pieces of

each type of thread are tested under similar

conditions. Type A thread had an average of tensile

strength of 86.7 kg with a standard deviation of 6.28

kg, while type B had an average tensile strength of

77.8 with a standard deviation of 5.61 kg. Test the

manufacturer’s

claim

using

a

0.05

level

of

significance.

A group of students got the following scores in a test; 6, 9, 12, and 18. Consider samples of size 2 that can be selected from the population. What is the variance of the population?

Consider a population consisting of 2, 4, 6, 8 and 10. Suppose samples of size 3 are drawn from this population.

a. Describe the sampling distribution of the sample means

b. What are the mean and variance of the sampling distribution of the sample means? c. Construct a histogram for the sampling distribution.

Consider a population consisting of 2,6,8,0 and 1. Suppose samples of size 2 are drawn from this population. Find the Mean and Variance of the sampling distribution of sample means.

A population has mean 73.5 and standard deviation 2.5. Find the mean and standard deviation of X ̅ for samples of size 30.

If Johnny had 20 complete living room outfits, disregard color scheme, how many different sets of five complete outfits could be arranged?