JEE Mains · Maths · STD 11 - 8. sequence and series
The sum of the \(3^{rd}\) and the \(4^{th}\) terms of a \(G.P.\) is \(60\) and the product of its first three terms is \(1000\). If the first term of this \(G.P.\) is positive, then its \(7^{th}\) term is
- A \(7290\)
- B \(640\)
- C \(2430\)
- D \(320\)
Answer & Solution
Correct Answer
(D) \(320\)
Step-by-step Solution
Detailed explanation
Let \(a, ar\) and \(a{r^2}\) be the first three terms of \(G.P\) According to the question \(a\left( {ar} \right)\left( {a{r^2}} \right) = 1000 \Rightarrow {\left( {ar} \right)^3} = 1000 \Rightarrow ar = 10\) and…
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