MATH 300 - Statistics Milestone 2. Questions and Answers

MATH 300 - Statistics Milestone 2. Questions and Answers Statistics Milestone 2 1 Which of the following statements is NOT true about the normal distribution? The normal distribution can be described as “bell-shaped.” We only need to know the mean and standard deviation in order to completely describe a normal distribution. A large portion of the data is located near the center in a normal distribution. The normal distribution is symmetric about the mean. The normal distribution is an example of a bimodal distribution. RATIONALE The normal distribution is a bell-shaped symmetic distribution with only one peak. So it is not bi-modal (i.e. 2 modes), but is unimodal, which means it has 1 mode. CONCEPT Normal Distribution 2 Stan is looking at the statistics for his favorite baseball player, who has hit 25, 26, 32, 38, 43, 40, 28, 32, 34, and 42 home runs in ten seasons. Using this data set, match each value with the correct description. Mean=====C. 34 Median===B. 33 Mode=====A. 32 A. 32 B. 33 C. 34 RATIONALE The mode is the most frequently occurring data point. The number 32 occurs two times, which is more than any other number's frequency. The mean is equal to the sum of the values divided by how many numbers there are. When we add the total number of home runs, we get 340. There were 10 seasons, so the mean can be calculated by th CONCEPT Mean, Median, and Mode 3 Erica is performing an experiment that requires her to weigh multiple samples. The masses of her samples are found to be normally distributed with a mean of 157g and a standard deviation of 5.2g. If Erica wants to convert her data to a standard normal distribution, which of the following statements is true? The new mean would be 1, and the standard deviation would be 0. The new mean would be 0, and the standard deviation would be 1. The new mean would be 1, and the standard deviation would be 5. The new mean would be 0, and the standard deviation would be 5. RATIONALE The mean and standard deviation for a standard normal is always 0 and 1. It is standardized since it takes all the raw data and converts them into z-scores. CONCEPT Standard Normal Distribution 4 Select the true statement for the following data set that has a mean of 5: