Question

My Notes You may need to use the appropriate appendix table or technology to answer this question. The following results are for independent random samples taken from two populations. Sample 1 Sample 2 ₂ = 20 | n₂ = 30 * - 22.7 -20.1 $1 = 2.2 $2 = 4.8 (a) What is the point estimate of the difference between the two population means? (Use x - ) 25 (b) What is the degrees of freedom for the distribution? (Round your answer down to the nearest integer.) (C) At 95% confidence, what is the margin of error? (Round your answer to one decimal place) (0) What is the confidence interval for the ofference between the two population means? ( U X, Round your answers to one decimal place 10 Subord Answer Practice Anomor Version 15 o tvoe here to search

Answer 1

solution:-

(a) point estimate

=> (x1-x2) = (22.7-20.1) = 2.6

(b) degrees of freedom for t distribution

=> (n1+n2)-2 = (20+30)-2 = 48

(c) at 95% confidence the t value with degrees of freedom from t table is = 2.011

margin of error = t * sqrt(s1^2/n1 + s2^2/n2)

= 2.011 * sqrt((2.2^2/20)+(4.8^2/30))

= 2.0

(d) confidence interval

=> point estimate +/- margin of error

=> 2.6 +/- 2.0

=> 0.6 to 4.6