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OpenStax, Introductory Business Statistics 2e §11.2 Test of a Single Variance · Exercise 26 · Statistics · Chi-square tests

Test of a Single Variance · Exercise 26

According to an avid aquarist, the average number of fish in a 20-gallon tank is 10, with a standard deviation of two. His friend, also an aquarist, does not believe that the standard deviation is two. They count the number of fish in 15 other 20-gallon tanks. Based on the results that follow, do you think that the standard deviation is different from two? Data: 11; 10; 9; 10; 10; 11; 11; 10; 12; 9; 7; 9; 11; 10; 11

This is an open-ended exercise: its source gives no single answer.

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OpenStax, Introductory Business Statistics 2e · §11.2 Test of a Single Variance · Exercise 26

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