Mathematics (AS & A Level) · Oct / Nov 2025 · Paper 51 · Question 4
9709
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The question as text
Bag A contains 8 red marbles and 3 blue marbles. Bag B contains 4 red marbles and 1 blue marble. A marble is chosen at random from bag A. If the marble chosen is red, it is discarded. If the marble chosen is blue, it is placed in bag B. A marble is then chosen at random from bag B. If the marble chosen is red, it is discarded. If the marble chosen is blue, it is placed in bag A. A marble is now chosen at random from bag A.
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4(a)[3]
4(b)[2]
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