In studying a random sample of 20 automotive batteries, the confidence interval (0.22,0.33) was constructed for the populati
on standard deviation of the batteries' reserve capacity in hours. This population standard deviation should be less than 0.26 hour. Does the confidence interval suggest that the variation in the batteries' reserve capacities is at an acceptable level? Explain your reasoning.
From the question, we are given a random sample of 20 automotive batteries, a confidence interval =(0.22,0.33). Also, the population standard deviation is said to be less than 0.26 hour.
The confidence interval does NOT suggest that the variation in the batteries' reserve capacities is at an acceptable level.
REASON: If you look at the confidence interval, we can see that it contains the value for the standard deviation that is 0.26 and even MORE value than 0.26.
This does not give us any suggestion that the standard deviation is less than 0.26.
It's equal to -15 because you are dividing by an negative and if it's only 1 negative number in your equation then your answer will be a negative and if it's 2 negatives then it would be a positive answer