Unit 4 · Statistics and Probability
8 Blue out of 16 — "Certain"? "Equally Likely"?
Lesson 6 of 6
About this lesson
16 discs: 5R, 2G, 8B, 1Y. Statement 1 (certain blue) fails — P(blue)=½≠1. Statement 2 (equally likely blue or not blue) is true — P(blue)=8/16=½=P(not blue). Statement 3 (possible yellow) is true — P(yellow)=1/16>0. Answer: 2 and 3 only.
Chapters
Question
Oliver has a box of 16 coloured discs.
- 5 discs are red.
- 2 discs are green.
- 8 discs are blue.
- 1 disc is yellow.
He picks one disc at random from the box.
Which of these statements are correct?
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It is certain that he picks a blue disc.
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It is equally likely that he picks a blue disc or does not pick a blue disc.
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It is possible for him to pick a yellow disc.
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