The basketball teams calculate the number of points scored by all athletes in every game. Suppose the average is usually 15, with a standard deviation, sigma = 2.5. Last year they calculated the averages before game play stopped for 36 games, and found the mean = 16.1. They want to see if this is significantly different from the usual amount. True or False - The correct hypothesis test to use in this situation would be a test of means using a Z computed test statistic. O True O False

A standardized​ exam's scores are normally distributed. In a recent​ year, the mean test score was 1471 and the standard deviation was 317. The test scores of four students selected at random are 1900​,1200​,2200​,and 1370. Find the​ z-scores that correspond to each value and determine whether any of the values are unusual.

On an intelligence​ test, the mean number of raw items correct is 236 and the standard deviation is 39. What are the raw​ (actual) scores on the test for people with IQs of​ (a) 119​, ​(b) 81​, and​ (c)100​? To do this​ problem, first figure the Z score for the particular IQ​ score; then use that Z score to find the raw score. Note that IQ scores have a mean of 100 and a standard deviation of 15.   ​(a) What is the raw​ (actual) score on the test for people with an IQ of 119​?

Deanna is the principal at a Midwestern middle school and wants to know the average IQ of all female, seventh grade students.  She does not know anything about what the population distribution looks like.  She took a simple random sample of 31 seventh-grade girls in her school and found the average IQ score in her sample was 105.8 and the standard deviation was 15. Using the sample standard deviation above to estimate the population standard deviation, what is the minimum sample size needed for a 99.5% confidence interval to have a margin of error of no more than 2.3?

IF THE VARIANCE OF A POPULATION IS 0.75, THE STANDARD DEVIATION MUST BE?

Exam scores in a large class are normally distributed with a mean of 55 and standard deviation of 10. The teacher decides to boost the scores by adding 20 points to everyone’s score.  Elizabeth’s original score on the exam was 75, so her new score is 95. The z-score corresponding to her new score (relative to the other new scores) will be: