Link probability fractions, decimals and percentages; compare simulated results and expected variation.
Example 1
A fair spinner has 4 equal-sized sectors, of which 2 are red. What is the probability of red as a percentage?
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Answer: 50
- All sectors are equally likely, so P(red)=42=0.5.
- Multiply by 100 to express this as 50%.
Example 2
A fair six-sided die is rolled 60 times. The event is rolling a number at most 2. What is the expected number of times this event occurs?
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Answer: 20
- There are 2 favourable equally likely faces out of 6.
- Expected frequency =60×62=20. This is a prediction; an actual experiment can differ.
Example 3
A fair spinner has 10 equal-sized sectors, of which 5 are red. What is the probability of red as a percentage?
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Answer: 50
- All sectors are equally likely, so P(red)=105=0.5.
- Multiply by 100 to express this as 50%.