Use the given confidence level and sample data to find (a) the margin of errorand (b) the confidenceinterval for the population mean. Assume that the population has a normal distribution.
Weight lost on a diet: 99% confidence; n = 61, x = 3.0 kg. s = 5.7 kg.
(a) E = ______kg (Round to one decimal place)
(b) What is t
In a random sample of six microwave ovens, the mean repair cost was $90.00 and the standard deviation was $11.00. Assume the variable is normally distributed and use a t-distribution to construct a 90% confidenceinterval for the population mean u. What is the margin of error of u?
The 90% confidenceinterval for the popula
A random sample of 81 credit sales in a department store showed an average sale of $68.00. Historically, it is known that the standard deviation of the population is $27.00. a) determine the standard error of the mean, b) with a 0.95 probability, what can be said about the margin of errorand c) what is the 95% confidence interv
Consider the formula used for any confidenceintervaland the elements included in that formula. What happens to the confidenceinterval if you (a) increase the confidence level, (b) increase the sample size, or (c) increase the margin of error? Only consider one of these changes at a time. Explain your answer with words and by
Calculate the correlation of the data set (3,2), (3,3), (6,4).
A 95% confidenceinterval for the average miles per gallon for all cars of a ginven type is 32.1 plus/minus 1.8. The interval is based on a sample of 40 randomly selected cars.
What units represent the margin of error?
Suppose you want to decrease the margin of
1. Consider the following test of whether the coin is fair. Toss a coin three times, if the coin lands whether all heads or tails, reject the Ho: p=1/2. If P=4/5, What is the probability of type II error for this procedure?
2. A sample of 350 orders for takeout at a local pizzeria found out that the average cost of order w
Compute a 95% confidenceinterval for the population mean, based on the sample 25, 27, 23, 24, 25, 24 and 59. Change the number from 59 to 24 and recalculate the confidenceinterval. Using the results, describe the effect of an outlier or extreme value on the confidenceinterval.
Find the critical value Zc necessary to form a confidenceinterval at the given level of confidence.
The new Twinkle bulb has a mean life of hours with a standard deviation Q = 35 hours. A random sample of 50 light bulbs is selected from inventory. The sample mean was found to be X(with a line above X) 500 hours.