| Exam Board | OCR |
|---|---|
| Module | C1 (Core Mathematics 1) |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Indices and Surds |
| Type | Simplify numerical surds |
| Difficulty | Easy -1.2 This is a straightforward surd simplification requiring students to factor 22.5 = 225/10 = (15/√10)² or equivalently 22.5 = 2.25 × 10, then simplify to get 1.5√10. It's a routine C1 exercise testing basic surd manipulation with no problem-solving required, though the decimal form makes it slightly less trivial than integer-based surd questions. |
| Spec | 1.02b Surds: manipulation and rationalising denominators |
Express $\sqrt{22.5}$ in the form $k\sqrt{10}$. [4]
\hfill \mbox{\textit{OCR C1 Q2 [4]}}