This task is about comparing theoretical with experimental outcomes.
Practical Task
Throw the three coins together. Score a "head" as 1 point and a "tail" as 2 points.
a) | i) | Add the three scores together, repeat this a total of 80 times and record your results in the tally chart below. | ||||||||||
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ii)
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Complete the table below using the information from the tally chart above.
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b)
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There are eight ways that the coins can come up. They are:
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The probability of getting the three coins summing to 3 (i.e., three heads) is 1⁄8.
Complete the table of probabilities. The first one has been done for you.
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c)
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Use the table above to predict how many times you would expect to get each of the following sums if the three coins were thrown 80 times.
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i)
ii)
iii)
iv)
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A sum of 3? __________
A sum of 4? __________
A sum of 5? __________
A sum of 6? __________
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d) |
Write a statement comparing the expected frequencies in c) with what you actually got in the experiment in part a) ii).
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e)
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Why may the results in a) ii) and c) be different?
Give two reasons.
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