Page 44 - Probability Demystified

P. 44

CHAPTER 2 Sample Spaces 33

EXAMPLE: When two dice are rolled, ﬁnd the probability that one of the
numbers is a 6.

SOLUTION:

There are 11 outcomes that contain a 6. They are (1, 6), (2, 6), (3, 6), (4, 6),
(5, 6), (6, 6), (6, 5), (6, 4), (6, 3), (6, 2), and (6, 1). Hence,

11
P(one of the numbers is a six) ¼
36

PRACTICE

1. When a card is selected at random, ﬁnd the probability of getting

a. A 9.
b. The ace of diamonds.
c. A club.
2. When a card is selected at random from a deck, ﬁnd the probability
of getting
a. A black card.
b. A red queen.
c. A heart or a spade.
3. When a card is selected at random from a deck, ﬁnd the probability
of getting
a. A diamond or a face card.
b. A club or an 8.
c. A red card or a 6.

4. When two dice are rolled, ﬁnd the probability of getting
a. A sum of 7.
b. A sum greater than 8.
c. A sum less than or equal to 5.

5. When two dice are rolled, ﬁnd the probability of getting
a. A 5 on one or both dice.
b. A sum greater than 12.
c. A sum less than 13.

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