Foundation June 2021 Paper 1 Q17
17 Here are the first 4 terms of an arithmetic sequence.
85 79 73 67
Find an expression, in terms of \(n\), for the \(n\)th term of the sequence.
(2)
| Scheme | Marks |
|---|---|
| \(91 - 6n\) | B2 |
| (2) | |
| (2 marks) |
Notes
B2: for a correct answer in any form eg \(91 - 6 \times n\) or \(-6n + 91\) or \(85 + (n - 1)(-6)\) oe
(B1 for \(-6n + k\) oe (\(k\) may be zero or absent))
NB: award full marks for eg \(x = 91 - 6n\) or \(n\)th term \(= 91 - 6n\) but only B1 for \(n = 91 - 6n\)