The monthly earnings of computer programmers are normally ...

[audragclark]

The monthly earnings of computer programmers are normally distributed with a mean of 4,000 . If only 1.7 of programmers have monthly incomes of less than 2,834, what is the standard deviation of the monthly earnings of the computer programmers?

Question 2

The makers of a soft drink want to identify the average age of its consumers. A sample of 16 consumers is selected. The average age in the sample was 22.5 years with a standard deviation of 5 years. Assume the population of consumer ages is normally distributed.
 a. Construct a 95 confidence interval for the average age of all the consumers.
  b. Construct an 80 confidence interval for the average age of all the consumers.
  c. Discuss why the 95 and 80 confidence intervals are different.

[raili21]

Answer to Question 1

550

Answer to Question 2

a. 19.836 to 25.164
b. 20.824 to 24.176
c. As the level of confidence increases, the confidence interval gets wider.

[audragclark]

Thank you

[raili21]

Happy to help you