Which of these is NOT a set of Bernoulli trials?

Throwing a die 8 times and noting whether it shows a 6Correct answerYour answerDrawing 4 balls one by one with replacement from the same bag, and noting red or notCorrect answerYour answerAsking 10 people chosen at random from a large town whether they own a carCorrect answerYour answerDrawing 4 balls one by one without replacement from a bag of 6 red and 4 blue, and noting red or notCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

Bernoulli trials need the same probability of success on every trial, independently.
Without replacement, the chance of red changes after each draw ( $\frac{6}{10}$ , then $\frac{5}{9}$ or $\frac{6}{9}$ ), so those draws are not Bernoulli trials.

Worth noting

In a large town, picking 10 people barely changes the share of car owners, so those count as Bernoulli trials.

Concept: Recognising Bernoulli trials
Typical timeTypical: 90 s
Your timeYours: —

The rule this testsBernoulli trials

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Ten questions from Binomial & Poisson Distributions, at your own pace.

Which of these is NOT a set of Bernoulli trials?

Explanation