Exercise · ZW-RANDOM-SAMPLE-001 · ★☆☆ Basic
A coin with \(P(\text{heads})=\tfrac14\) is tossed 3 times independently. What is the probability of the sequence heads, tails, heads?
Choose one option.
Show answer
- C. \(\tfrac{3}{64}\)
Explanation
By independence the probabilities multiply: \(\tfrac14\cdot\tfrac34\cdot\tfrac14=\tfrac{3}{64}\).
Review the concept: Random sample
A random sample of size \(n\) is a set of \(n\) independent random variables \(X_i\), all with the same distribution, that represent \(n\) observations from a population.
\[X_1,\dots,X_n\ \text{independent and identically distributed}\]
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