4) A college admissions officer takes a simple random sample of 100 entering freshmen and computes their mean mathematics SAT score to be 466. Assume the population 90. standard deviation is o = Construct a 98% confidence interval for the mean mathematics SAT score for the entering freshmen class. A) (441, 491) B) (376, 556) C) (445, 487) D) (464, 468)

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The brain volumes (cm³) of 20 brains have a mean of 1113.7 cm³ and a standard deviation of 128.9 cm³. Use the give standard deviation and the range rule of thumb to identify the limits separating values that are significantly low or significantly high. For such data, would a brain volume of 1361.5 cm³ be significantly high? 3 Significantly low values are cm³ or lower. (Type an integer or a decimal. Do not round.)

Reebok is analyzing all the data from different stores across the globe to shut down the stores which are not having profit.After a lot of analysis, the mean and standard deviations were found. What is the percentage of distribution which is expected within two standard deviations from the mean to each side? Choose :  A) 68%     B) 65%    C) 99.7%     D) it depends on how big the sample size is.

6. Suppose that 100 females at a gym are randomly selected and asked their weights, in pounds. The mean is 137, the median is 125, and the standard deviation is approximately 23. What can you conclude? Read carefully and select one of the following: a) On average, each female's weight in the sample is approximately 23 pounds different from the mean. b) On average, each female's weight in the sample is approximately 23 pounds different from the median. c) On average, each female's weight in the sample is approximately 23% different from the mean. d) On average, each female’s weight in the sample is approximately 23% different from the median.

Announcements for 83 upcoming engineering conferences were randomly picked from a stack of IEEE Spectrum magazines. The mean length of the conferences was 3.96 days, with a standard deviation of 1.24 days. Assume the underlying population is normal.   1)In words define the random variables x and x̅  X is the mean length from a sample of 83 engineering conferences and x̅ is the length of an engineering conference.  X is the length of an engineering conference and x̅  is the mean length from a sample of 83 engineering conferences. X is the number of engineering conferences and x̅ is the mean number of engineering conferences listed in IEEE spectrum magazine. X is the mean number of engineering conferences listed in IEEE spectrum magazine and x̅ is the number of engineering conferences.    2)Which distribution should you use for this problem? Explain your choice. The student’s t-distribution should be used because the sample mean is smaller than 30.   The student’s t-distribution…