| Date | May 2010 | Marks available | 1 | Reference code | 10M.2.sl.TZ1.2 |
| Level | SL only | Paper | 2 | Time zone | TZ1 |
| Command term | Write down | Question number | 2 | Adapted from | N/A |
Question
Consider the arithmetic sequence 3, 9, 15, … , 1353 .
Write down the common difference.
Find the number of terms in the sequence.
Find the sum of the sequence.
Markscheme
common difference is 6 A1 N1
[1 mark]
evidence of appropriate approach (M1)
e.g. un=1353
correct working A1
e.g. 1353=3+(n−1)6 , 1353+36
n=226 A1 N2
[3 marks]
evidence of correct substitution A1
e.g. S226=226(3+1353)2 , 2262(2×3+225×6)
S226=153228 (accept 153000) A1 N1
[2 marks]
Examiners report
Most candidates did well on this question. Any errors were usually arithmetic in nature but candidates were able to obtain follow-through marks on errors made in earlier parts.
Most candidates did well on this question. Any errors were usually arithmetic in nature but candidates were able to obtain follow-through marks on errors made in earlier parts.
Most candidates did well on this question. Any errors were usually arithmetic in nature but candidates were able to obtain follow-through marks on errors made in earlier parts.
