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 65 students in the high school and found a mean savings of 2700 dollars with a standard deviation of 700 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 65 students in the high school and found a mean savings of 2700 dollars with a standard deviation of 700 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 and formula: Identify the values given in the problem and the formula to use for the margin of error at the 95% confidence level.We know:- The mean savings (μ) is $2700.- The standard deviation (σ) is $700.- The sample size (n) is 65 students.- The z-score for a 95% confidence level is approximately 1.96 for a normal distribution.The margin of error (E) can be calculated using the formula:E=z×(σ/n)
Calculate standard error: Calculate the standard error of the mean σ/n by dividing the standard deviation by the square root of the sample size.Standard error (SE) = σ/nSE = 700/65SE ≈700/8.0623SE ≈86.77
Calculate margin of error: Calculate the margin of error (E) by multiplying the z-score by the standard error.E=z×SEE=1.96×86.77E≈170.07
Round margin of error: Round the margin of error to the nearest whole number.E≈170.07Rounded E=170
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