Question

In: Statistics and Probability

A sample of 7 adult elephants had an average weight of 11900 pounds. The standard deviation...

A sample of 7 adult elephants had an average weight of 11900 pounds. The standard deviation for the sample was 24 pounds. What is the 99% confidence interval of the population mean for the weights of adult elephants? Assume that the variable is normally distributed.

Expert Solution

n = sample size = 7

s = sample standard deviation = 24

The formula for a confidence interval

E = margin of error

df = degrees of freedom = n-1 = 7 - 1 = 6

c = level of confidence = 0.990 ( We converted 99% in to decimal )

We use t table to find t critical value

We look for row headed df = 6 and column headed c = 0.990

So we get t critical value

E =33.62674323

Final answer:-

The confidence interval of the population mean for the weights of adult elephants is ( 11866.37326, 11933.62674 )

Or

Note: If they mention any rounding then round according to instruction.

orchestra answered 3 years ago

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