Question

Consider the following results for independent random samples taken from two populations.

Sample 1	Sample 2
n 1 = 20	n 2 = 40
x 1 = 22.1	x 2 = 20.9
s 1 = 2.4	s 2 = 4.7

1. What is the point estimate of the difference between the two population means (to 1 decimal)?
2. What is the degrees of freedom for the t distribution (round down your answer to nearest whole number)?
3. At 95% confidence, what is the margin of error (to 1 decimal)?
4. What is the 95% confidence interval for the difference between the two population means (to 1 decimal)? If your answer is negative value, entre minus (-) sign. Use z-table.
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Answer 1