The nth term of an arithmetic progression is given by \(a_n=7-4n\). Which statement about this AP is correct?
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Answer and explanation
Correct answer: The common difference is \(-4\).
In \(a_n=a+(n-1)d\), the coefficient of \(n\) is the common difference \(d\). Here it is \(-4\), so \(d=-4\) and the terms decrease. As a quick check, putting \(n=1\) gives the first term \(3\), not \(7\).
Frequently asked questions
What is the correct answer to this question?
The common difference is \(-4\).
Why is this the correct answer?
In \(a_n=a+(n-1)d\), the coefficient of \(n\) is the common difference \(d\). Here it is \(-4\), so \(d=-4\) and the terms decrease. As a quick check, putting \(n=1\) gives the first term \(3\), not \(7\).
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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