| Exam Board | OCR MEI |
|---|---|
| Module | S1 (Statistics 1) |
| Year | 2006 |
| Session | January |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Combinations & Selection |
| Type | Basic committee/group selection |
| Difficulty | Easy -1.2 This is a straightforward application of basic combinations and permutations formulas (C(12,7) and 7!) with no problem-solving required. It's a standard textbook exercise testing recall of when to use combinations vs permutations, making it easier than average for A-level. |
| Spec | 5.01a Permutations and combinations: evaluate probabilities5.01b Selection/arrangement: probability problems |
| Answer | Marks |
|---|---|
| \(\binom{12}{7} = 792\) | M1 A1 |
| Answer | Marks |
|---|---|
| \(7! = 5040\) | M1 A1 |
# Question 6:
**(i)**
$\binom{12}{7} = 792$ | M1 A1 |
**(ii)**
$7! = 5040$ | M1 A1 |
---6 A band has a repertoire of 12 songs suitable for a live performance. From these songs, a selection of 7 has to be made.\\
(i) Calculate the number of different selections that can be made.\\
(ii) Once the 7 songs have been selected, they have to be arranged in playing order. In how many ways can this be done?
\hfill \mbox{\textit{OCR MEI S1 2006 Q6 [4]}}