# 6 Questions

An IQ test is designed so that the mean is 100 and the standard deviation is 20 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of statistics students such that it can be said with 95?% confidence that the sample mean is within 5 IQ points of the true mean. Assume that sigmasequals=20 and determine the required sample size using technology. Then determine if this is a reasonable sample size for a real world calculation.

A programmer plans to develop a new software system. In planning for the operating system that he will? use, he needs to estimate the percentage of computers that use a new operating system. How many computers must be surveyed in order to be 90?% confident that his estimate is in error by no more than four percentage points question mark s? Complete parts? (a) through? (c) below.
?a) Assume that nothing is known about the percentage of computers with new operating systems.
(Round up to the nearest? integer.)
b. Assume that a recent survey suggests that about 95?% of computers use a new operating system.
(Round up to the nearest? integer.)

Using the simple random sample of weights of women from a data? set, we obtain these sample? statistics: nequals=35 and x overbarxequals=141.54 lb. Research from other sources suggests that the population of weights of women has a standard deviation given by sigmasequals=31.42 lb.
a. Find the best point estimate of the mean weight of all women.
b. Find a 9090?% confidence interval estimate of the mean weight of all women.
a. The best point estimate is nothing lb.
?(Type an integer or a? decimal.)
b. The 90?% confidence interval estimate is nothing lb less than0.10.1

Identify the test statistic for this hypothesis test.
The test statistic for this hypothesis test is nothing.
?(Round to two decimal places as? needed.)

A food safety guideline is that the mercury in fish should be below 1 part per million? (ppm). Listed below are the amounts of mercury? (ppm) found in tuna sushi sampled at different stores in a major city. Construct a 98?% confidence interval estimate of the mean amount of mercury in the population. Does it appear that there is too much mercury in tuna? sushi?0.59 0.70 0.10 0.89 1.32 0.52 0.79

In a study of 786 randomly selected medical malpractice? lawsuits, it was found that 518 of them were dropped or dismissed. Use a 0.01 significance level to test the claim that most medical malpractice lawsuits are dropped or dismissed.
Which of the following is the hypothesis test to be? conducted?
A.
Upper H 0 : p equals 0.5H0: p=0.5
Upper H 1 : p greater than 0.5H1: p>0.5
B.
Upper H 0 : p equals 0.5H0: p=0.5
Upper H 1 : p less than 0.5H1: p<0.5 C. Upper H 0 : p equals 0.5H0: p=0.5 Upper H 1 : p not equals 0.5H1: p?0.5 D. Upper H 0 : p not equals 0.5H0: p?0.5 Upper H 1 : p equals 0.5H1: p=0.5 E. Upper H 0 : p less than 0.5H0: p<0.5 Upper H 1 : p equals 0.5H1: p=0.5 F. Upper H 0 : p greater than 0.5H0: p>0.5
Upper H 1 : p equals 0.5H1: p=0.5
What is the test? statistic?
zequals=nothing
?(Round to two decimal places as? needed.)

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