In the AP (121,109,97,\ldots), which is the last term greater than (-75)?
Answer and explanation
Correct answer: (-71)
Here, the first term is \(a=121\) and the common difference is \(d=-12\). Thus, \(a_n=121-12(n-1)\). We get \(a_{17}=-71\), and the next term is \(a_{18}=-83\). Since \(-71>-75\) but \(-83<-75\), the last term greater than \(-75\) is \((-71)\). \((-83)\) is a close distractor, but it is less than \(-75\). Exam tip: In a decreasing AP, check the two consecutive terms on either side of the given limit.
Frequently asked questions
What is the correct answer to this question?
(-71)
Why is this the correct answer?
Here, the first term is \(a=121\) and the common difference is \(d=-12\). Thus, \(a_n=121-12(n-1)\). We get \(a_{17}=-71\), and the next term is \(a_{18}=-83\). Since \(-71>-75\) but \(-83<-75\), the last term greater than \(-75\) is \((-71)\). \((-83)\) is a close distractor, but it is less than \(-75\). Exam tip: In a decreasing AP, check the two consecutive terms on either side of the given limit.
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.
