random sample has been taken from a normal population and two confidence intervals constructed using exactly the same data. The

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2 years ago

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two CIs are (38.02, 61.98) and (39.95, 60.05). (a) What is the value of the sample mean

1 answer:

Zepler [3.9K] · Answer 1 · 2022-09-25T16:21:44+03:00

The sample mean of the random sample is 50

The margin of error (E) is the amount of error allowed in the random sample.

The confidence interval (CI) is given by:

CI = μ ± E = (μ - E, μ + E)

Given a confidence interval of (38.02, 61.98), hence:

μ - E = 38.02 (1)

μ + E = 61.98 (2)

Hence solving equations 1 and 2 simultaneously gives:

μ = 50, E = 11.98

Hence the sample mean of the random sample is 50