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[accordion] [toggle title=”Prerequisites” state=”closed”]- N1c – Equivalent fractions and simplifying fractions (essential)
- R9a – Converting between fractions, decimals and percentages (desirable)
Theoretical probability
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Click the tabs for extension tasks…
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[tab title=”Task 1″]
There are 400 seats in a cinema theatre, numbered from 1 to 400. You buy a movie ticket and are allocated a seat. You have an equal chance of being allocated to each seat. Are you
You pick a date at random from this calendar year. Each date is equally likely to be picked. Is the probability that the date you pick falls on a Monday going to equal precisely \(\dfrac{1}{7}\)? Explain your answer.
A bag contains only red, green, and blue marbles. Assuming marbles are well-mixed, the probability of picking a green marble is double the probability of picking a red marble, and the probability of picking a blue marble is three times the probability of picking a green marble.
There are 400 seats in a cinema theatre, numbered from 1 to 400. You buy a movie ticket and are allocated a seat. You have an equal chance of being allocated to each seat. Are you
- more likely to be allocated to a seat numbered under 200 than a seat numbered over 200?
- less likely to be allocated to a seat numbered under 200 than a seat numbered over 200?
- equally likely to be allocated to a seat numbered under 200 as a seat numbered over 200?
You pick a date at random from this calendar year. Each date is equally likely to be picked. Is the probability that the date you pick falls on a Monday going to equal precisely \(\dfrac{1}{7}\)? Explain your answer.
Hover for answer: No; the number of days in the year is not divisible by 7.
[/tab] [tab title=”Task 3″]A bag contains only red, green, and blue marbles. Assuming marbles are well-mixed, the probability of picking a green marble is double the probability of picking a red marble, and the probability of picking a blue marble is three times the probability of picking a green marble.
- What is the lowest possible number of marbles in the bag?
- What is the second lowest possible number of marbles in the bag?
- What is the third lowest possible number of marbles in the bag? What do you notice?
- 9 marbles
- 18 marbles
- 27 marbles; total number must be a multiple of 9
Hover for answers:
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