An IQ test is designed so that the mean is 100 and the standard deviation is 16 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of the residents of a state if you want to be 95% confident that the sample mean is within 3 IQ points of the true mean. The required sample size is. (Round up to the nearest whole number.)

A study was commissioned to find the mean weight of the residents in certain town. The study found the mean weight to be 174 pounds with a margin of error of 7 pounds. Which of the following is a reasonable value for the true mean weight of the residents of the town?

Suppose you have already calculated the mean, the average deviation, and the standard deviation of the weights in pounds of 20 third-graders.  a. if these weights were converted to kilograms and the mean and the average deviation were once again calculated, would the second average deviation be (numerically) less than, greater than, or equal to the first average deviation? Explain your answer. b. If the standard deviation of these weights were calculated in kilograms, would it be (numerically) less than, greater than, or equal to the first standard deviation? Explain your answer

A successful basketball player has a height of 6 feet 11 ​inches, or 211 cm. Based on statistics from a data​ set, his height converts to the z score of 5.17. How many standard deviations is his height above the​ mean?

The mean for a data set is 61. The standard deviation is 4, and the z-score is -0.34. Find the raw score. What is the raw score? (Type an integer or a decimal.)

We have a population of frogs with a mean weight of 0.9 pounds. We select four frogs and find their average weight. What do you suppose it will be?

For an Economics test the mean score is 100 and the standard deviation is 10, and for an Accounting test the mean score is 50 and the standard deviation is 4. You are given the test scores of a student who took both tests. Determine on which test the student had a better score. Enter E if the student did better on the Economics test Enter A if the student did better on the Accounting test Enter S if the student did relatively the same on both tests.   A student scores 125.6 on the Economics test and 60.2 on the Accounting test. The student did better/same on                test.

Find the value of the standardized test statistic.

There are two major tests of readiness for college, the ACT and the SAT. ACT scores are reported on a scale from 1 to 36. The distribution of ACT scores is approximately Normal with mean = 21.5 and standard deviation = 5.4. SAT Scores are reported on a scale from 600 to 2400. The distribution of SAT scores is approximately Normal with mean = 1498 and standard deviation = 316. (b) Joshua scores 17 on the ACT. Anthony scores 1030 on the SAT. Assuming both tests measure the same thing, who has the higher score? Report both z-scores. (c) What is the purpose of finding the z-scores for both the ACT and SAT scores?

Use the expression in the accompanying discussion of sample size to find the size of each sample if you want to estimate the difference between proportions of men and women who own smartphones. Assume that you want 95​% confidence that your error is no more than 0.03.