Exercise · ZW-RANDOM-SAMPLE-002 · ★☆☆ Basic
A fair die is rolled 4 times. What is the probability that all 4 results are even?
Choose one option.
Show answer
- A. \(\tfrac{1}{16}\)
Explanation
Each roll is even with probability \(\tfrac12\) and rolls are independent: \((\tfrac12)^4=\tfrac1{16}\).
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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