WBJEE · Maths · Sequences and Series
Six numbers are in AP such that their sum is 3 . The first term is 4 times the third term. Then, the fifth term is
- A -15
- B -3
- C 9
- D -4
Answer & Solution
Correct Answer
(D) -4
Step-by-step Solution
Detailed explanation
Let the numbers be \(a-5 d t, a-3 d, a-d, a+d, a+3 d, a+5 d\) Also, given \(T_{1}=4 T_{3},\) where \(T_{1}, T_{3}\) are respectively, first and third terms of AP. \(\Rightarrow \quad a-5 d=4(a-d)\) \(\Rightarrow \quad d=-3 a=-\frac{3}{2}\) \(\therefore\) The fifth term…
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