30 The manager of the local Walmart Superright is studying the number of items purchased by...
SCCoast, an Internet provider in the Southeast, developed the following frequency distribution on the age of Internet users. Find the mean and the standard deviation. (Round squared deviations to nearest whole number and final answer to 2 decimal places.) Age (years) Frequency 10 up to 20 3 20 up to 30 7 30 up to 40 18 40 up to 50 20 50 up to 60 12 Mean Standard deviation
SCCoast, an Internet provider in the Southeast, developed the following frequency distribution on the age of Internet users. Find the mean and the standard deviation. (Round squared deviations to nearest whole number and final answer to 2 decimal places.) Age (years) Frequency 10 up to 20 3 20 up to 30 7 30 up to 40 18 40 up to 50 20 50 up to 60 12 Mean Standard deviation
The IRS was interested in the number of individual tax forms prepared by small accounting firms. The IRS randomly sampled 41 public accounting firms with 10 or fewer employees in the Dallas-Fort Worth area. The following frequency table reports the results of the study. 12.5 Number of Clients points 10 up to 14 14 up to 18 18 up to 22 22 up to 26 26 up to 30 12 eBook 12 Print References Estimate the mean and the standard...
The historical returns on a portfolio had an average return of 21 percent and a standard deviation of 29 percent. Assume that returns on this portfolio follow a bell-shaped distribution. a. Approximately what percentage of returns were greater than 79 percent? (Round your answer to the nearest whole percent.) b. Approximately what percentage of returns were below –66 percent? (Round your answer to 1 decimal place.) ____________________________________________________________________________________________________________________________ The following relative frequency distribution was constructed from a population of 400. Calculate...
Consider a sample with 10 observations of 11, –3, 8, 8, 10, 1, –2, 13, 8, and –4. Use z-scores to determine if there are any outliers in the data; assume a bell-shaped distribution. (Round your answers to 2 decimal places. Negative values should be indicated by a minus sign.) The z-score for the smallest observation The z-score for the largest observation There are outliers or no outliers in the data. The historical returns on a portfolio had...
Consider a sample with 10 observations of 11, –3, 8, 8, 10, 1, –2, 13, 8, and –4. Use z-scores to determine if there are any outliers in the data; assume a bell-shaped distribution. (Round your answers to 2 decimal places. Negative values should be indicated by a minus sign.) The z-score for the smallest observation The z-score for the largest observation There are outliers or no outliers in the data. The historical returns on a portfolio had...
Determine the mean, median, and standard deviation of the following frequency distribution: (Round the final answers to 2 decimal places.) Class Frequency 0 to under 5 5 to under 10 10 to under 15 15 to under 20 20 to under 25 4 Mean Median Standard deviation
Find the mean, median, mode, population standard deviation and variance of the given data: Items 3 5 6 9 10 12 15 Frequency 1 4 2 12 5 4 2 Mean=9.03 Median= 9 Mode 9 Population standard= 4 Variance= 16 Mean=9,03 Median= 9 Mode- 9 Population standard deviation=5 Variance= 25 Mean=9.03 Median= 9 Mode= 9 Population standard deviation= 6 Variance= 36 Mean=9.03 Median= 9 Mode= 9 Population standard deviation=2.8 Variance= 7.7
1. Forty randomly selected students were asked the number of pairs of sneakers they owned. Let X = the number of pairs of sneakers owned. The results are as follows. X Frequency 1 2 2 5 3 6 4 13 5 13 6 1 A. Find the sample standard deviation, s. (Round your answer to two decimal places.) answer is NOT 1.22 B. Complete the columns of the chart. (Round your answers to three decimal places.) Fill in chart for...
Each of 169 newly manufactured items is examined and the number of scratches per item is recorded (the items are supposed to be free of scratches), yielding the following data: Number of scratches per item 0 1 2 3 4 5 6 7 Observed frequency 24 31 48 31 14 12 4 5 Let X = the number of scratches on a randomly chosen item, and assume that X has a Poisson distribution with parameter ?. (a) Find an unbiased...