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Sequential Draws Without Replacement

EasyStatistics & Probability00:00
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Welcome to your interview.

The question is on your right: Sequential Draws Without Replacement. Take a moment with it first.

Talk your thinking through with me if you like - when you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes). Discussion and graded submissions share your five interviewer interactions, so spend them well.

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Problem

Scenario

You have a box with 3 red marbles and 7 blue marbles. You draw two marbles one after the other, without putting the first one back.

Question

What is the probability that both marbles are blue?