Telephone Calls A researcher knew that before cell phones, a person made on average 2.8 calls per day. He believes that the number of calls made per day today is higher. He selects a random sample of 33 individuals who use a cell phone and asks them to keep track of the number of calls that they made on a certain day. The mean was 3.1. At a=0.10, is there enough evidence to support the researcher's claim? The standard deviation for the population found by a previous study is 0.9. Assume that the variable is normally distributed. Use the critical value method with tables.

Telephone Calls A researcher knew that before cell phones, a person made on average 2.8 calls per day. He believes that the number of calls made per day today is higher. He selects a random sample of 33 individuals who use a cell phone and asks them to keep track of the number of calls that they made on a certain day. The mean was 3.1. At a=0.10, is there enough evidence to support the researcher's claim? The standard deviation for the population found by a previous study is 0.9. Assume that the variable is normally distributed. Use the critical value method with tables.

Calculus For The Life Sciences

2nd Edition

ISBN:9780321964038

Author:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.

Publisher:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.

Chapter13: Probability And Calculus

Section13.3: Special Probability Density Functions

Problem 16E

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