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Statistics and probability

Course: Statistics and probability > Unit 7

Lesson 6: Addition rule
Math
Statistics and probability
Probability
Addition rule
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Adding probabilities

CCSS.Math: HSS.CP.B.7
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Problem

26 customers are eating dinner at a local diner. Of the 26 customers, 20 order coffee, 8 order pie, and 7 order coffee and pie. Using this information, answer each of the following questions.
Let A be the event that a randomly selected customer orders coffee and B be the event that a randomly selected customer orders pie.
What is P, left parenthesis, A, right parenthesis, the probability that a customer orders coffee?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a proper fraction, like 1, slash, 2 or 6, slash, 10
  • an improper fraction, like 10, slash, 7 or 14, slash, 8
  • a mixed number, like 1, space, 3, slash, 4
What is P, left parenthesis, B, right parenthesis, the probability that a customer orders pie?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a proper fraction, like 1, slash, 2 or 6, slash, 10
  • an improper fraction, like 10, slash, 7 or 14, slash, 8
  • a mixed number, like 1, space, 3, slash, 4
What is P, left parenthesis, A, start text, space, a, n, d, space, end text, B, right parenthesis, the probability that a customer orders coffee and pie?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a proper fraction, like 1, slash, 2 or 6, slash, 10
  • an improper fraction, like 10, slash, 7 or 14, slash, 8
  • a mixed number, like 1, space, 3, slash, 4
What is P, left parenthesis, A, start text, space, o, r, space, end text, B, right parenthesis, the probability that a customer orders coffee or pie?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a proper fraction, like 1, slash, 2 or 6, slash, 10
  • an improper fraction, like 10, slash, 7 or 14, slash, 8
  • a mixed number, like 1, space, 3, slash, 4
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