A researcher is interested in finding a 95% confidence interval for the mean number of times per day that college students text. The study included 107 students who averaged 29.1 texts per day. The standard deviation was 18.2 texts. Round answers to 3 decimal places where possible. a. To compute the confidence interval use a ? ✓ distribution. b. With 95% confidence the population mean number of texts per day is between texts. and c. If many groups of 107 randomly selected members are studied, then a different confidence interval would be produced from each group. About percent of these confidence intervals will contain percent will not contain the true the true population number of texts per day and about population mean number of texts per day.

According to the College Board, scores on the math section of the SAT Reasoning college entrance test for the class of 2010 had a mean of 516 and a standard deviation of 116. Assume that they are roughly normal.One of the quartiles of the scores from the math section of the SAT Reasoning test is 438. The other quartile is _______.

Five students took a self-confidence test. Their deviation scores were –4, +3, +1, –2, and +2. Assuming that these scores com form a normaldistribution, which deviation represents the highest raw score?

The mean GPA of all 45,038 students at Uneeda College is 3.21. A random sample of 50 GPAs from the school has a mean of 3.16. Is the value 3.21 a parameter or a statistic?

Use z scores to compare the given values.   The tallest living man at one time had a height of 256cm. The shortest living man at that time had a height of 114.6 cm. Heights of men at that time had a mean of 174.87 cm and a standard deviation of 7.57 cm. Which of these two men had the height that was more​ extreme?   Since the z score for the tallest man is z=____ and the z score for the shortest man is z=_____​, the (Shortest/tallest) man had the height that was more extreme. ​(Round to two decimal​ places.)

A researcher is interested in finding a 90% confidence interval for the mean number of times per day that college students text. The study included 97 students who averaged 25.5 texts per day. The standard deviation was 20.5 texts. Round answers to 3 decimal places where possible. b. With 90% confidence the population mean number of texts per day is between ______ and _______  texts. c. If many groups of 97 randomly selected members are studied, then a different confidence interval would be produced from each group. About _______ percent of these confidence intervals will contain the true population number of texts per day and about ___________ percent will not contain the true population mean number of texts per day.

Consider the data from the Anthropology 105 class.  The mean for women is 64.33 in and the standard deviation is 2.64 in. The average height of men in the US is approximately 5ft 10in. What proportion of women represented here are shorter than the average man?

Researchers collected information on the body parts of a new species of frog. The thumb length for the female frog has a mean of 8.28 mm and a standard deviation of 0.78 mm. Let x denote thumb length for a female specimen.   a. Find the standardized version of x. b. Determine and interpret the​ z-scores for thumb lengths of 10.3 mm and 7.1 mm. Round your answers to two decimal places.   a. Find the standardized version of x.   z=enter your response here