1. You flip a coin three times.
The possible outcomes of this random experiment are,
S = {(HHH), (HHT), (HTH), (THH), (HTT), (TTH), (THT), (TTT)}
n (S) = 8
(a) What is the probability of getting heads on only one of your flips?
The cases favorable to the event E1 of getting heads on only one of your flips are,
E1 = {(HTT), (TTH), (THT)}
n (E1) = 3
P (E1) = n (E1) / n (S) = 3/8 = 0.375
(b) What is the probability of getting heads on at least one flip?
The cases favorable to the event E2 of getting heads on only one of your flips are,
E2 = {(HHH), (HHT), (HTH), (THH), (HTT), (TTH), (THT)}
n (E2) = 7
P (E2) = n (E2) / n (S) = 7/8 = 0.875