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Statistics and probability

Course: Statistics and probability > Unit 9

Lesson 8: More on expected value
Math
Statistics and probability
Random variables
More on expected value
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Expected value with calculated probabilities

CCSS.Math: HSS.MD.A.3
Google Classroom
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Problem

Laila is playing a game where there are 4 blue markers and 6 red markers in a box. She is going to pick 3 markers, and replace each marker immediately after she picks it.
If she picks all 3 red markers, she will win a total of dollar sign, 400. If the first 2 markers she picks are blue, she will win a total of dollar sign, 300. Under any other outcome, she will win dollar sign, 0.
What is the expected value of Laila's winnings?
Round your answer to the nearest cent.
dollar sign
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
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