3. Below is the number of texts per day for a random sample of students from...

3. Below is the number of texts per day for a random sample of students from last semester. (Population normal enough.)

a. Create the 95% confidence interval for both sets of data. Is there evidence that the population means are different? Under 19 years old: 250, 15, 200, 10, 15, 50, 20, 150, 63, 15, 7, 20, 35, 4, 20 At least 19 years old: 100, 20, 40, 5, 30, 100, 100, 65, 5, 25, 20, 50, 10, 10

b. How many more people at least 19 years old would you need to sample to be within 10 texts of the true mean?

Expert Solution

a)

there is no evidence that the population means are different. As the limits of the first group coincide with the other.

2) MArgin of error = 10

for 95% confidence

sample of 14 was taken

so you require 50-14=36 more to sample to be within 10 texts of the true mean

orchestra answered 2 years ago

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