A-LevelMathematicsProbability and statisticsOct/Nov 2025Paper 5 Q45 Marks
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. (a) Complete the tree diagram below by entering all the remaining outcomes and probabilities. [3] [Tree diagram with some branches and probabilities: Bag A Red (8/11) Bag B (empty for now) Bag A (empty for now) Blue (3/11) Bag B Red (4/6) Bag A (empty for now) Blue (2/6) Bag A (empty for now) ]
✓ Correct Answer
The correct answer is —. This question tests the candidate's understanding of probability and statistics within the Mathematicssyllabus. The examiner's mark scheme requires...
📋 Examiner Report & Trap Analysis
Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...
🔒
Unlock the Examiner's Answer
Sign up for free to reveal the correct answer, the official mark scheme breakdown, and the examiner trap analysis for this question.
Sign Up Free to Unlock →Join thousands of Cambridge students already using Oracle Prep