Higher November 2024 Paper 3 Q13
13 A bag contains one £5 note, one £10 note, one £20 note and one £50 note.
Amaan picks two of the notes at random without replacement.
Work out the probability that he has picked at least £30 [2 marks]
| Answer | Mark | Comments |
|---|---|---|
| Alternative method 1 | ||
| \(4 \times 3\ (\div 2)\) or \(12\ (\div 2)\) or 6 or correct list of all possible combinations or all possible qualifying combinations (5,10) (5,20) 5,50 (10,5) 10,20 10,50 (20,5) 20,10 20,50 50,5 50,10 50,20 or (5,10) (5,20) 5,50 10,20 10,50 20,50 | M1 | number of possible combinations may be implied by the correct total for each combination |
| \(\dfrac{4}{6}\) or \(\dfrac{8}{12}\) | A1 | oe fraction, decimal or percentage with M1 awarded |
| Alternative method 2 | ||
\(\dfrac{1}{4} \times \dfrac{1}{3}\) or \(\dfrac{1}{12}\) | M1 | picking £5 first |
| \(\dfrac{4}{6}\) or \(\dfrac{8}{12}\) | A1 | oe fraction, decimal or percentage with M1 awarded |
Additional guidance
Decimals or percentages should be rounded or truncated to 2dp or better
In Alt 1, combinations may be seen in a grid, table or other diagram
In Alt 1, do not accept repeat combinations or incorrect combinations for M1