Q. For the following set of data, find the sample standard deviation, to the nearest thousandth.59,68,40,56,36,70,20
List data set and calculate mean: List the data set and calculate the mean (average).Data set: 59,68,40,56,36,70,20Mean (μ)=759+68+40+56+36+70+20Mean (μ)=7349Mean (μ)=49.857
Find squared differences: Subtract the mean from each data point and square the result to find the squared differences.Squared differences:(59−49.857)2=83.796(68−49.857)2=329.796(40−49.857)2=97.796(56−49.857)2=37.796(36−49.857)2=193.796(70−49.857)2=406.796(20−49.857)2=889.796
Sum squared differences: Sum the squared differences.Sum of squared differences = 83.796+329.796+97.796+37.796+193.796+406.796+889.796Sum of squared differences = 2039.572
Calculate variance: Divide the sum of squared differences by the sample size minus one to find the variance.Sample size n = 7Variance s2 = 2039.572/(7−1)Variance s2 = 2039.572/6Variance s2 = 339.929
Find sample standard deviation: Take the square root of the variance to find the sample standard deviation.Sample standard deviation s = 339.929Sample standard deviation s≈18.440
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