A random sample of 18 purchases showed the amounts in the table(in $). The mean is $45.06 and the standard deviation is $23.35.

a) How many degrees of freedom does thet-statistic have?

b) How many degrees of freedom would thet-statistic have if the sample size had been 2?

80.81

22.04

23.04

5.34

24.15

65.34

65.60

26.59

27.92

10.11

49.61

71.62

55.48

55.74

75.78

36.81

57.03

58.04

a) Thet-statistic has

degrees of freedom.

(Simplify youranswer.)

b) If the sample size had been 2, thet-statistic would have

degrees of freedom.

(Simplify youranswer.)