JEE Mains · Maths · STD 11 - 8. sequence and series
The number of terms in an \(A .P.\) is even ; the sum of the odd terms in it is \(24\) and that the even terms is \(30\). If the last term exceeds the first term by \(10\frac{1}{2}\) , then the number of terms in the \(A.P.\) is
- A \(4\)
- B \(8\)
- C \(12\)
- D \(16\)
Answer & Solution
Correct Answer
(B) \(8\)
Step-by-step Solution
Detailed explanation
Let \(a,d,\) nad \(2n \) be the frist term, common difference and total number of terms of an A.P. respectively i.e. \(a + \left( {a + d} \right) + \left( {a + 2d} \right) + ... + \left( {a + \left( {2n - 1} \right)d} \right)\) No. of even terms \(=n\), of odd terms \(=n\) Sum…
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