10'4 Using Addition With Probability

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10.4 Using Addition With Probability
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Essential Question

• How do I find the probability of mutually
  exclusive or inclusive events?

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• Consider a situation with 2 mutually exclusive
• outcomes tossing a coin.
• Find the probability of it landing heads up.
• 2. Find the probability of it landing tails up.
• 3. Find the probability of it landing heads or
  tails up.
• 4. Compare your answer to Exercise 3 with your
  answers to Exercises 1 and 2.

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Probability of A or B Let A and B represent
events in the same sample space. If A and B
are mutually exclusive events, P(A or B) P(A)
P(B). If A and B are inclusive events, P(A
or B) P(A) P(B) - P(A and B).
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Find the probability of an event. A spinner is
divided into 10 congruent regions labeled 1 - 10.
Let A spinning an odd number, B spinning a
multiple of 4, and C spinning a multiple of 3.
A and B are mutually exclusive events.
A and C are inclusive events.
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Probability of the Complement of A Let A
represent an event in the sample space. P(A)
P(Ac) 1 P(A) 1 - P(Ac) P(Ac) 1 - P(A)
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A single card is drawn at random from a standard
52-card deck. Find each probability a. The card
is a heart or a club. b. The card is a heart or
an ace. c. The card is not an ace. d. The
card is not the king of clubs.
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Two number cubes are rolled, and the numbers on
the top faces are added. The table at right
shows the possible outcomes. Find each
probability. a. The sum is odd or greater than
11. b. The sum is less than 6 or greater than
10. c. The sum is even or less than 5. d. The
sum is less than 8 or a multiple of 6. 15. The
sum is less than 4 or a multiple of 5.
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An engineering consulting firm employs engineers,
accountants, and secretaries. The manager of the
firm is interested in the methods of
transportation that the employees use to travel
to work.

• Find the probability that a randomly selected
  employee is an engineer or a secretary.
• b. Find the probability that a randomly selected
  employee is an accountant or rides a bus to work.

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The girls varsity softball, basketball, and
volleyball teams at Greenfield High have 13
players, 10 players, and 11 players,
respectively. Some players are on more than
one team, as indicated in the diagram. If one of
these players is randomly selected, find the
probability that the player is on at least two
teams.