Question

Name: _____________________ Year 8____ Date: _____________
WALT: Compare estimated experimental probabilities with theoretical probabilities.
Q1. Anders wants to find the probability of scoring a total of at least 20 when he throws six dice.
a] What is the smallest and largest possible totals when six dice are thrown? Explain how you got
your answers.
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Anders runs a computer simulation and gets these results.

Number of throws of 6 dice 50 100 200 300 400 500
Frequency of 20 or more 26 57 119 186 245 311

b] Work out the experimental probability of scoring a total of at least 20 after 50, 100, 200, 300,
400 and 500 throws. Complete the table below. Give the probabilities in decimals.
Number of throws of 6 dice 50 100 200 300 400
Probability

c] Use your values from [b] to estimate the theoretical probability of scoring a total of at least 20.
Explain how you got your answer.
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Q2. “If you drop a piece of buttered bread, it is more likely to land buttered side down.”
Mia does an experiment to test this statement. He wants to estimate the probability that the bread
will land on buttered side down. Five people each drop a piece of bread 20 times.
Person dropping bread 20 times A B C D E
Number of times buttered side down 16 18 14 15 12

a] Explain why dropping the bread 20 times is not enough to give a reliable estimate.
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b] Combine all the results to get an experimental probability based on dropping the bread 100
times. Show working.

Five people repeat the experiment to get these results.

Person dropping bread 20 times A B C D E
Number of times buttered side down 15 14 10 12 19

c] Find an estimate based on the results so far. Show working.

d] Why is the answer to part C the most reliable estimate?
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Answer 1

Answer:

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