| Exam Board | OCR MEI |
|---|---|
| Module | S1 (Statistics 1) |
| Year | 2009 |
| Session | June |
| Marks | 5 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Combinations & Selection |
| Type | Committee with gender/category constraints |
| Difficulty | Moderate -0.8 This is a straightforward application of combinations with no conceptual challenges. Part (i) is direct calculation of C(25,5), and part (ii) requires multiplying C(14,3) × C(11,2). Both are standard textbook exercises requiring only recall of the combination formula with minimal problem-solving. |
| Spec | 5.01a Permutations and combinations: evaluate probabilities5.01b Selection/arrangement: probability problems |
2 There are 14 girls and 11 boys in a class. A quiz team of 5 students is to be chosen from the class.\\
(i) How many different teams are possible?\\
(ii) If the team must include 3 girls and 2 boys, find how many different teams are possible.
\hfill \mbox{\textit{OCR MEI S1 2009 Q2 [5]}}