1. WARM - UP
The American Red Cross says that about 45% of the US Population has Type O blood, 40% Type A, 11% Type B, and the rest Type AB.
a.) Selecting one individual, what is the probability that:
1. has Type AB blood?
2. has Type A or Type B?
3. is NOT Type O?
b.) Among four potential donors, what is the probability that:
1. all are Type O?
2. no one is Type AB?
3. at least one person is Type B?
P(AB) = 1 – P(OUAUB) =
0.04
P(AUB) =
0.51
P(OC) =
0.55
P(O∩O∩O∩O) =
0.041
P(ABC∩ABC∩ABC∩ABC) =
0.849
1 – P(BC∩BC∩BC∩BC) =
0.373

4. Monty Hall problem
Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, which always a goat. He then says to you, "Do you switch your choice or stay?” What should you do? Does it matter?

5. Monty Hall problem
1/3
2/3
2/3
Do NOT Switch Switch
Win = 33%
Win = 66%

6. Page 341: 20, 23, 27, 28, 31, 34

10. Monty Hall problem
Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, which always a goat. He then says to you, "Do you switch your choice or stay?” What should you do? Does it matter?

11. Monty Hall problem
Do NOT Switch Switch
Win = 33%
Win = 66%

12. More with Multiplication Rule
4. A password for a certain computer application MUST be exactly 5 characters long. (Character = Alphabet and Digits)
If the first character can not be a number, how many password combinations are possible if:
a.) you are NOT allowed to Repeat any character?
_____ _____ _____ _____ _____
b.) you are allowed to Repeat?
26 x x x x =
26 x x x x =