Question 1: A study of 60 turtles showed that the average number of times they hid in their shells was 45 times with a standard deviation of 25 times.
Develop a 95% confidence interval of the the mean times turtles hid in their shells.
a. 40.86688 to 49.1312
b. 39.6746 to 50.3253
c. 38.6741 to 51.3259
d. 44.2562 to 62.5454
Question 2: The average cost of tuition and room and board at a small private liberal arts college is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 225 small liberal arts colleges showed that the average cost per term is $8,745 with a standard deviation of $1,500. Let= .005. Calculated z= 2.45 What is the critical z value for this test?
a. +1.96
b. -1.96
c. +1.65
d. -1.65