Exercise · ZW-RANDOM-SAMPLE-005 · ★★☆ Intermediate
A coin with \(P(\text{heads})=0.3\) is tossed 4 times independently. What is the probability that all 4 are tails?
Choose one option.
Show answer
- C. \(0.2401\)
Explanation
Each tail has probability \(0.7\); by independence \(0.7^4=0.2401\).
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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