JEE Mains · Maths · STD 11 - 8. sequence and series
If the first term of an \(A.P.\) is \(3\) and the sum of its first \(25\) terms is equal to the sum of its next \(15\) terms, then the common difference of this \(A.P.\) is :
- A \(\frac{1}{4}\)
- B \(\frac{1}{5}\)
- C \(\frac{1}{7}\)
- D \(\frac{1}{6}\)
Answer & Solution
Correct Answer
(D) \(\frac{1}{6}\)
Step-by-step Solution
Detailed explanation
Sum of 1 st 25 terms \(=\) sum of its next 15 termss \(\Rightarrow\left( T _{1}+\ldots \ldots+ T _{25}\right)=\left( T _{26}+\ldots . .+ T _{40}\right)\) \(\Rightarrow\left( T _{1}+\ldots . .+ T _{40}\right)=2\left( T _{1}+\ldots \ldots+ T _{25}\right)\)…
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