Worked Example 3: Decreasing Sequence
Part of nth Term · GCSE GCSE Mathematics revision
This study notes covers Worked Example 3: Decreasing Sequence within nth Term for GCSE Mathematics. Revise nth Term in Algebra for GCSE Mathematics with 11 exam-style questions and 4 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 6 of 8 in this topic. Use this study notes to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 6 of 8
Practice
11 questions
Recall
4 flashcards
Worked Example 3: Decreasing Sequence
Find the nth term of: 20, 17, 14, 11, 8, ...
Step 1 Find the common difference
17 − 20 = −3
Common difference d = −3
Step 2 Start the formula
nth term starts with −3n
Step 3 Compare and adjust
−3n gives: −3, −6, −9, −12...
Sequence is: 20, 17, 14, 11...
20 − (−3) = 23, so add 23
Answer: nth term = −3n + 23 (or 23 − 3n)
Keep building this topic
Read this section alongside the surrounding pages in nth Term. That gives you the full topic sequence instead of a single isolated revision point.
Practice Questions for nth Term
The nth term of a sequence is 3n + 2. What is the 5th term?
A student claims that 50 is a term in the sequence with nth term 3n + 1. Show whether this claim is correct.
Quick Recall Flashcards
11 questions on nth Term — practise free
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