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Hypothesis testing newborn infant weights

Questions 1- 10 refer to the following:
The average weight of newborn infants at a hospital is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0,8.8.,6.8, 8.4, and 6.6 pound.

1. What is the null hypothesis? Ho: The average weight of a baby is 6.6

2. What is the alternate hypothesis? HA: The average weight of a baby is not equal 6.6

3. What are the degrees of freedom? _____6______

4. If alpha is 0.05, what is the critical value? _____1.2_______

5. What is the sample mean? _____7.557_______

6. What is the sample variance? ___1.386________

7. What is the sample standard deviation? ____1.177__________

8. What is the t value? _____1.94________

9. If t = 2.16, what is the decision rule for a statistical significant change in average weights at birth at the 5% level of significance? ______________

10. If the t value is 2.66, what is the decision for a significant change on the average birthrate at a 5% level of significance? ______________