| Exam Board | Edexcel |
|---|---|
| Module | C1 (Core Mathematics 1) |
| Marks | 3 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Arithmetic Sequences and Series |
| Type | Sigma notation: arithmetic series evaluation |
| Difficulty | Easy -1.2 This is a straightforward application of standard summation formulas for arithmetic series. Students need only recognize the arithmetic sequence, apply the formula S_n = n/2(first term + last term) or split into Σ3r + Σ4, requiring minimal problem-solving beyond direct formula recall. |
| Spec | 1.04g Sigma notation: for sums of series |
| Answer | Marks | Guidance |
|---|---|---|
| AP: \(a = 7, l = 94\) | B1 M1 A1 | (3 marks) |
| \(S_{10} = \frac{10}{2}(7 + 94) = 15 \times 101 = 1515\) |
AP: $a = 7, l = 94$ | B1 M1 A1 | (3 marks)
$S_{10} = \frac{10}{2}(7 + 94) = 15 \times 101 = 1515$ | |Evaluate
$$\sum_{r=1}^{20} (3r + 4).$$
[3]
\hfill \mbox{\textit{Edexcel C1 Q1 [3]}}