The TOEFL scores of 8 students were researched before and after the training. The results are given in the table: Student 1 2 3 4 5 6 7 8 before 75 65 85 80 81 86 81 85 after 89 73 96 78 86 90 90 92 а) Find 95% confidence interval for the d - difference of the scores of 8 students before and after the training, b) Do the data support that the average score is changed at the α=0.05? c) Do the data support that the average score is increased by more than 4 points at the α=0.05?

The TOEFL scores of 8 students were researched before and after the training. The results are given in the table: Student 1 2 3 4 5 6 7 8 before 75 65 85 80 81 86 81 85 after 89 73 96 78 86 90 90 92 а) Find 95% confidence interval for the d - difference of the scores of 8 students before and after the training, b) Do the data support that the average score is changed at the α=0.05? c) Do the data support that the average score is increased by more than 4 points at the α=0.05?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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