Question 1

Use the EMPIRICAL RULE to complete the problems in this section. The Acme Company manufactures widgets. The distribution of widget weights is bell-shaped. The widget weights have a mean of 39 ounces and a standard deviation of 7 ounces. Use the Standard Deviation Rule, also known as the Empirical Rule. Suggestion: sketch the distribution in order to answer these questions. 68% of the widget weights lie between _____________ and____________

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Question 2

Use the EMPIRICAL RULE to complete the problems in this section. In a mid-size company, the distribution of the number of phone calls answered each day by each of the 12 receptionists is bell-shaped and has a mean of 63 and a standard deviation of 10. Using the empirical rule, what is the approximate percentage of daily phone calls numbering between 53 and 73? Do not enter the percent symbol. ans = _________ %

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Question 3

The heights of American adult males are normally distributed with a mean of 177 cm and a standard deviation of 7.4 cm. Use the Empirical Rule to find the range of heights that contain approximately (a) 68% of the data _______cm --_____________ cm (b) 95% of the data __________ cm -- _____________ cm (c) 99.7% of the data __________ cm -- _____________ cm

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Question 4

If babies' weights are normally distributed with a mean of 3.23 kg and a standard deviation of 0.87 kg, find the range of weights that contain approximately (a) 68% of the data ___________ kg -- ___________ kg (b) 95% of the data __________kg -- __________ kg (c) 99.7% of the data _______kg -- _______kg

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Question 5

The results of a common standardized test used in psychology research is designed so that the population mean is 105 and the standard deviation is 20. A subject earns a score of 67. What is the z-score for this raw score? z-score =

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Question 6

Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the height of a man with a z-score of 1.6 (to 2 decimal places)

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Question 7

The results of a common standardized test used in psychology research is designed so that the population mean is 160 and the standard deviation is 10. A subject earns a score of 169. What is the z-score for this raw score? z-score =

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Question 8

The average resting heart rate of a population is 85 beats per minute, with a standard deviation of 14 bpm. Find the z-scores that correspond to each of the following heart rates. Round your answers to the nearest hundredth, if necessary. (a) 109 bpm z = (b) 75 bpm z =

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Question 9

In a mid-size company, the distribution of the number of phone calls answered each day by each of the 12 receptionists is bell-shaped and has a mean of 55 and a standard deviation of 3. Using the empirical rule (as presented in the book), what is the approximate percentage of daily phone calls numbering between 52 and 58? Do not enter the percent symbol. ans = %