WBJEE · Maths · Sequences and Series
Six positive numbers are in GP, such that their product is 1000 . If the fourth term is 1 , then the last term is
- A 1000
- B 100
- C \(\frac{1}{100}\)
- D \(\frac{1}{1000}\)
Answer & Solution
Correct Answer
(C) \(\frac{1}{100}\)
Step-by-step Solution
Detailed explanation
Let the six terms of GP are \[ \frac{a}{r^{5}} \cdot \frac{a}{r^{3}}, \frac{a}{r}, a r, a r^{3}, a r^{5} \] Now, according to the question \(\frac{a}{r^{5}} \cdot \frac{a}{r^{3}} \cdot \frac{a}{r} \cdot a r \cdot a r^{3} \cdot a r^{5}=1000\)…
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