An arithmetic progression has first term 11 and common difference -4. Which of the following expressions correctly represents its nth term?
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Answer and explanation
Correct answer: \(a_n=11-4(n-1)\)
The nth term of an AP is \(a_n=a_1+(n-1)d\). Substituting \(a_1=11\) and \(d=-4\) gives option A. In option B, putting \(n=1\) gives 7, not 11. Exam tip: always test \(n=1\) to verify the first term.
Frequently asked questions
What is the correct answer to this question?
\(a_n=11-4(n-1)\)
Why is this the correct answer?
The nth term of an AP is \(a_n=a_1+(n-1)d\). Substituting \(a_1=11\) and \(d=-4\) gives option A. In option B, putting \(n=1\) gives 7, not 11. Exam tip: always test \(n=1\) to verify the first term.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Arithmetic Progressions (AP). Topic: Finding the $n$th term of an AP.
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