Unit 4 · Statistics and Probability
24 Balls — Which Probability Statements Are True?
Lesson 3 of 6
About this lesson
Now let's tackle one of the most common probability formats in OC MR: a question that gives you a bag of coloured items and asks you to judge whether several probability statements are true or false. The key skill is checking each statement independently and knowing the complement rule cold.
Chapters
Question
A bag contains 24 balls: 10 red, 6 blue, 8 green.
One ball is drawn at random. Three students make statements:
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Picking a red ball is more likely than picking a blue ball.
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Picking a green ball and picking a blue ball are equally likely.
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The chance of picking a ball that is not red is the same as the chance of picking a blue or green ball.
Which statements are correct?
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