4400 Higher November 2004 Paper 4 Q8
8 The \(n\)th term of a sequence is given by this formula.
\[n\text{th term} = 20 - 3n\](a) Work out the 8th term of the sequence. (1)
(b) Find the value of \(n\) for which \(20 - 3n = -22\) (2)
Here are the first five terms of a different sequence.
\[8 \qquad 11 \qquad 14 \qquad 17 \qquad 20\](c) Find an expression, in terms of \(n\), for the \(n\)th term of this sequence. (2)
| Scheme | Marks |
|---|---|
| −4 | B1 |
| (1) |
Notes
B1: cao
| Scheme | Marks |
|---|---|
| \(3n = 20 + 22\) or \(-3n = -22 - 20\) | M1 |
| 14 | A1 |
| (2) |
Notes
A1: cao
| Scheme | Marks |
|---|---|
| \(3n + 5\) oe | B2 |
| (2) | |
| (5 marks) |
Notes
B2: B1 for \(3n\) oe seen