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Flip to reveal answersWhat is the expected number of occurrences in n trials?
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All 9 Flashcards — Expected number
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Question
What is the expected number of occurrences in n trials?
Answer
n × P, where P is the probability of the event each trial.
Question
Can an expected number be a decimal?
Answer
Yes — it is a long-run average, not a single count.
Question
What do you do if the probability isn't given directly?
Answer
Find P first (from a sample space, proportion or table), then multiply by n.
Question
What does the expected number actually represent?
Answer
The average number of occurrences you'd expect over many repeats.
Question
How do you find an expected total amount?
Answer
Multiply the average per trial (expected value) by the number of trials n.
Question
Expected number of sixes in 60 rolls of a fair die?
Answer
60 × 1/6 = 10.
Question
If P(win) = 0.25 over 40 games, expected wins?
Answer
40 × 0.25 = 10.
Question
Is the expected value guaranteed in one run?
Answer
No — it is a long-run average, so a single run may differ.
Question
Expected number of heads in 100 fair coin tosses?
Answer
100 × 1/2 = 50.
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Full study notes for Expected number
Topic 4.5 hub
Probability basics
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Math AA SL exam skills
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