Thirty-two 1-Liter specimens of water were drawn from the water supply for a city and the...

Thirty-two 1-Liter specimens of water were drawn from the water supply for a city and the concentration of lead in the specimen was measured. The average level of lead was 7.3 µg/Liter, and the standard deviation for the sample was 3.1 µg/Liter. Using a significance level of 0.05, do we have evidence the mean concentration of lead in the city’s water supply is less than 10 µg/Liter? Find:

The t critical value ?

If the true mean equals the null mean the probability the test statistic value will be less than the t critical value is ?

Our test result cannot be

(a) A correct decision

(b) a Type I error

IF given below are some possible values for the true mean (given in units of µg/Liter). Which value will give the LARGEST probability of a Type II error?

(a) 7.2 (b) 8.6 (c) 9.4 (d) 11.3

IF given below are some possible values for the true mean (given in units of µg/Liter). Which value will give the SMALLEST probability of a Type II error?

(a) 7.2 (b) 8.6 (c) 9.4 (d) 11.3

Solutions

Expert Solution

orchestra answered 1 year ago

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