A study of a local high school tried to determine the mean amount of money that each student had saved. The study surveyed a random sample of 71 students in the high school and found a mean savings of 2600 dollars with a standard deviation of 1500 dollars. At the 95% confidence level, use the normal distribution/empirical rule to estimate the margin of error for the mean, rounding to the nearest whole number. (Do not write ± ).Answer:
Q. A study of a local high school tried to determine the mean amount of money that each student had saved. The study surveyed a random sample of 71 students in the high school and found a mean savings of 2600 dollars with a standard deviation of 1500 dollars. At the 95% confidence level, use the normal distribution/empirical rule to estimate the margin of error for the mean, rounding to the nearest whole number. (Do not write ± ).Answer:
Identify values: Identify the values given in the problem.We are given:- The mean savings of the sample (xˉ) = \(2600\)\(\newline\)- The standard deviation of the sample (s) = 1500- The sample size (n) = 71- The confidence level (95%)
Determine z-score: Determine the z-score that corresponds to the 95% confidence level.For a 95% confidence level, the z-score that corresponds to the confidence interval is approximately 1.96. This value is obtained from a standard normal distribution table or z-score table.
Calculate SEM: Calculate the standard error of the mean (SEM).The standard error of the mean is calculated using the formula:SEM = nsWhere s is the standard deviation and n is the sample size.SEM = 71$1500SEM ≈8.426$1500SEM ≈$177.83
Calculate ME: Calculate the margin of error (ME) using the z-score and the standard error of the mean.ME=z×SEMME=1.96×$177.83ME≈$348.53
Round margin: Round the margin of error to the nearest whole number. ME≈$(349)
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