Conditional Probability
19
Medium
0/4

A box contains only blue pens and black pens. There are 8 blue pens and 4 black pens.

Chloe takes at random a pen from the box. She does not put the pen back in the box.

Chloe takes at random a second pen from the box.

a.

Complete the probability tree diagram.

A probability tree diagram for two pens. The first selection has two branches: Blue and Black, each with a dotted line for probability. The second selection has four branches: Blue, Black, Blue, and Black, each with a dotted line for probability.

[2]
b.

Work out the probability that Chloe takes two pens of the same colour.

[2]

Conditional Probability Questions

Practise OCR GCSE Maths Conditional Probability with exam-style questions for Foundation and Higher tier. 28 questions, matched to the OCR GCSE Maths (J560) specification and written in the written papers style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.

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Conditional Probability Questions

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