Describe possible outcomes and compare records of repeated chance experiments.
Example 1
A coin is tossed 20 times in each of two trials. There are 9 heads in the first trial and 10 in the second. Which statement is justified?
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Answer: Chance results can vary from one trial to another
- Heads and tails are possible on each toss.
- A short set of trials need not be split equally, and the next toss is not forced by earlier results.
Example 2
Two groups each toss a coin 20 times. Group A records 6 heads; Group B records 13 heads. How many more heads did Group B record?
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Answer: 7
- Compare the recorded counts: 13−6=7.
- The groups can get different results even when they use fair coins.
Example 3
A coin is tossed 20 times in each of two trials. There are 8 heads in the first trial and 13 in the second. Which statement is justified?
Show worked answer
Answer: Chance results can vary from one trial to another
- Heads and tails are possible on each toss.
- A short set of trials need not be split equally, and the next toss is not forced by earlier results.