Answer: 10 3.4641 2.8965 12.8965 Step-by-step explanation: Given: 10, 8, 12, 15, 13, 11, 6, 5 c = 95% a. The point estimate of the population mean is the sample mean. The mean is the sum of all values divided by the number of values: x = 10 + 8 + 12 + 15 + 13 + 11 + 6 + 5 /8 = 80/8 = 10 b. The point estimate of the population standard deviation is the sample standard deviation. The variance is the sum of squared deviations from the mean divided by n - 1. The standard deviation is the square root of the variance: s = /(10 – 10)^2 +.... + (5– 10)^2/8 – 1 s = 3.4641 c. Determine the t-value by looking in the row starting with degrees of freedom df = n-1 = 8 –1 = 7 and in the column with = (1 – c)/2 = 0.025 in table : t_/2 = 2.365 The margin of error is then: E = t_/2 * s/√n = 2.365 x s 3.4641/ √8 = 2.8965 d. The confidence intent)] then becomes: 7.1035 = 10 – 2.8965 = x – E <u />
