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quester [9]
2 years ago
6

Exhibit 11-1 Last year, the standard deviation of the ages of the students at UA was 1.81 years. Recently, a sample of 10 studen

ts had a standard deviation of 2.1 years. We are interested in testing to see if there has been a significant change in the standard deviation of the ages of the students at UA. Refer to Exhibit 11-1. The test statistic is
Mathematics
1 answer:
rewona [7]2 years ago
3 0

Answer:

test statistic = 12.115

Step-by-step explanation:

Given data :

std = 2.1 years

n = 10

( std )^2 = 4.41

<u>determine the test statistic</u>

apply a two-tailed test ( chi squared test for one population variance )

test statistic

λ^2 = \frac{(n-1)s^2}{3.2761}   ( Referring to Exhibit 11-1 )

      = ( 10 - 1 )*(2.1)^2 / 3.2761

      = 12.115

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