MHT CET · Maths · Sequences and Series
The sum of first four terms of a G.P. is 160 and the common ratio is 3 , then the \(4^{\text {th }}\)
term is
- A 118
- B 100
- C 108
- D 102
Answer & Solution
Correct Answer
(C) 108
Step-by-step Solution
Detailed explanation
\(a, a r, a r^{2}, a r^{3}\)
\(2=3\)
\(\frac{a\left(\varepsilon^{4}-1\right)}{(\varepsilon-1)}=160\)
Solving these we get \(a=4\)
\(a \varepsilon^{3}=t_{4}=108\)
\(2=3\)
\(\frac{a\left(\varepsilon^{4}-1\right)}{(\varepsilon-1)}=160\)
Solving these we get \(a=4\)
\(a \varepsilon^{3}=t_{4}=108\)
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