Stat 100

[BarTopDancer]

Halp! I'm pretty sure I did this all wrong. I read everything I have and I can't figure it out. Can someone explain where I went wrong?

3. Suppose studies have shown that approximately 20% (.2) of Americans regularly engage in exercise (at least 3 times per week).

a. If one American is randomly selected, what is the probability that he or she does not regularly engage in exercise? Set up calculation.

1 - .20 = .80

The probability that a randomly selected American does not engage in regular exercise is 80%

b. If three Americans are randomly selected, what is the probability that all three regularly engage in exercise? Set up the calculation.

1 - .20 = .80
.80 x 3 = 2.4

The probability that three randomly selected Americans engage in regular exercise is 2.4

c. What assumption is being made in part b above?

The assumption being made in part B is that the events are mutually excclusive.

d. If two Americans are randomly selected, what is the probability that the first American regularly engages in exercise while the second American does not regularly engage in exercise? Set up the calculation.

1 - .20 = .80
.80 x .20 = .16 because the two events are independent

Make sure that the values are in the correct order.