Question

Module 6: Problem 9 Previous Problem Problem List Next Problem (1 point) In the following questions, use the t-distribution to find a confidence interval for a difference in means #1 - Ma given the relevant sample results. Give the best point estimate for Hi-12, the margin of error, and the confidence interval. Assume the results come from random samples from a populations that are approximately normally distributed. Give your answers to 2 decimal places 1. A 80% interval for Mi - M2 using the sample results #1 = 6.2,81 = 6.2, 11 = 60 and 72 = 9.6,82 = 5.1, = 92. Use 1 = 1.289. a. Point estimate: b. Margin of error: c. Confidence interval:( 2. A 90% interval for Mi - Hz using the sample results #1 = 19.8,5 = 6.1. - 90 and 12 = 13.4,83 = 5.4.12 = 64. Use 1* = 1.655. a. Point estimates b. Margin of error: c. Confidence interval:( 3. A 90% interval for H1 - My using the sample results 21 = 29.8, 5, -6.8. = 96 and 7, - 20.2.82 = 5.8, = = 98. Uso * = 1.653 a Point estimate b. Margin of error: c. Confidence interval:( tombe df Lecture 10L - SL.pdf 30 MacBook Pro 000 DOO esc w3 $ 4 & 7 1 2 5 6 8

Answer 1

ni:60 +*: 1.289 Si= 6.2 a 71 = 6.2 X2=9.6 S2: S na = 92 -3.4 (و) x - x2 = 6.2 - 9.6 estimate point 522 3,2 ni cb) Margin of Exxort ME)- ** C + na ME -1.289 (6-2)2 + (5.132 92 60 1:24 confidence interval is (x - 72) Į ME -3.4 I 1.24 confidence interval is (-4.64 -2.16) X = 19.8 Si=6.1 niego 27 +* = 1.655 X2 = 13.4 52= 5.4 n2=64 ca) point estimate- Xi-X2= 19.8 - 13.4 = 6.4 2 (b) margin of Error (ME) : +* 18,2 S2 + ni กว. ME 31.655. 6.12 + 5.42 64 go ME 1.54

ce) The confidence interval is (XI-X2) + ME 6.4 I 1.54 confidence interval is ( 4.86 7.94 31 : 6.8 3) nie 96 1-653 Xi = 29.8 X2 - 20.2 ** S2. - 5.9 12:98 ca) point estimate = Xi-ja 29.8 - 20.23 9.6 * (b) S;? 52² margin of error (ME) + na = 1.653 6.8 5.82 96 98 ME 1.50 cc) The confidence interval is (XI-X2) I ME 9.6 + 1.50 Cool The confidence interval is ( 8. 11.10 )