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Adding probabilities

You might need: Calculator

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(A), the probability that a customer orders coffee?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a proper fraction, like 1/2 or 6/10
  • an improper fraction, like 10/7 or 14/8
  • a mixed number, like 1 3/4
What is P(B), the probability that a customer orders pie?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a proper fraction, like 1/2 or 6/10
  • an improper fraction, like 10/7 or 14/8
  • a mixed number, like 1 3/4
What is P(A and B), the probability that a customer orders coffee and pie?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a proper fraction, like 1/2 or 6/10
  • an improper fraction, like 10/7 or 14/8
  • a mixed number, like 1 3/4
What is P(A or B), the probability that a customer orders coffee or pie?
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a proper fraction, like 1/2 or 6/10
  • an improper fraction, like 10/7 or 14/8
  • a mixed number, like 1 3/4
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