(#1) The average life of a certain type and brand of battery is 75 weeks. The...

(#1) The average life of a certain type and brand of battery is 75 weeks. The average life of each of 9 randomly selected batteries is listed: 74.5, 75, 72.3, 76, 75.2, 75.1, 75.3, 74.9, 74.8

Assume the battery life distribution is normal. It is of interest to know if the sample data suggest the average life is greater than 75 weeks. Test the hypothesis that the average life of the batteries is greater than 75 weeks at level .05.

(a) Since .05 < p-value < 0.1, the sample data provides enough evidence that the average life of the batteries is greater than 75 weeks.

(b) Since .05 < p-value < 0.1, the sample data does not provide enough evidence that the average life of the batteries is greater than 75 weeks.

(c) Since p-value > 0.1, the sample data does not provide enough evidence that the average life of the batteries is greater than 75 weeks.

(d) Since p-value > 0.1, the sample data provides enough evidence that the average life of the batteries is greater than 75 weeks.

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orchestra answered 1 year ago

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