Discussion:
Q: Choose a person aged 19 to 25 years at random and ask, "how many times have you worked out in the past?" Call the response X for short. Based on a large sample survey, here is a probability model for the answer you will get:
Days 0 1 2 3 4 5 6 7
Probability 0.68 0.05 0.07 0.08 0.05 0.04 0.01 0.02
a) Verify that this is a legitimate discrete probability model
b) Describe the event X < 7 in words. What is P(X < 7)?
c) Express the event " worked out at least once" in terms of X. What is the probability of this event?