Statistics and Probability Answers

What is the proportion of the area of region between z =1 and z=

2

Suppose four cellphones are tested. Let D represent the defective cellphone and N for non defective cellphone. How many possible outcomes will occur from the experiment

Consider the population consisting of the values (4, 6, 8).

a. List down all the possible samples of size 2 with replacement.

b. Compute the mean of each sample.

c. Compute the mean of the sampling distribution of means.

d. Identify the probability of each sample.

e. Compute the population mean.

f. Compare the population mean with the mean of the sampling distribution of means.

The score of entrance examination takers who took a 600 item exam resemble a normal distribution with a mean of 220 and a standard deviations of 10. The coordinator would like to get the lowest 15% of thr scores and invite them for a retake examination. What range of scores indicates the inclusion in the retake of the exam?

A molding machine prepares a certain kind of car spare part with a target

diameter p = 42.23 mm. The machine has some variability, so the standard

deviation of the diameter is o = 0.003 mm. A sample of 10 spare parts is

inspected each hour for the process control purposes and record are kept of

the sample mean diameter. What will be the mean and standard deviation of

the number recorded?

1. The scores of the individual students on a national test have a normal

distribution with the mean 19.5 and standard deviation of 5.6. At Ramos High

School, 86 students took the test. If the scores at this school have the same

distribution as national scores, what are the mean and standard deviation of the

sample mean for 86 students?

The average number of milligrams of cholesterol in a cup of a certain

brand ice cream is 670 mg and standard deviation is 45 mg, Assume the

variable is normally distributed.

a. If a cup of ice cream is selected, what is the probability that the

cholesterol content will be more than 700 mg?

b. If a sample of 20 cups is selected what is the probability that the mean of

the sample will be larger than 700mg?

Supposed three coins are tossed.let Y be the random variable representing the number of tails that occur.find the values of the random variable Y.make a table to show the values of the random variable

The women's organization of barangay Ouano, organize a raffle draw. The members aim to sell 1,000 raffle tickets at Php 50 per ticket and each ticket has an equal chance of winning. The prizes are follows: 1st prize-24 inches Sony LED TV worth Php 10,000, 2nd prize-washing machine worth Php 5,000 and 3rd prize-grocery pack worth Php 2,500. Let X denote the net gain from the purchase of one ticket. Find the expected value of X, then interpret.

Solving Problems Involving Sample Size Determination

Apply the knowledge you obtained from the discussion by solving the given problems below.

1. A 95% confidence interval has to be created to estimate the mean volume of contents in the

bottles of Honey-Z. Assume that the population standard deviation is 30 ml. Calculate the sample

size needed if the margin of error is no more than:

a. 6 ml

b. 5 ml

c. 4ml

d. 3 ml

2. How large sample size is required to determine the mean IQ of seventh graders of Luis Palma

National High School within +5 points, population standard deviation of 25, and with the following

confidence level?

a. 98%

b. 95%.

c. 90%.

d. 80%.