The sum of \[1+\frac{2}{5}+\frac{3}{{{5}^{2}}}+\frac{4}{{{5}^{3}}}+... – McqOptions

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1.	The sum of \[1+\frac{2}{5}+\frac{3}{{{5}^{2}}}+\frac{4}{{{5}^{3}}}+...........\]upto \[n\] terms is [MP PET 1982]
A.	\[\frac{25}{16}-\frac{4n+5}{16\times {{5}^{n-1}}}\]
B.	\[\frac{3}{4}-\frac{2n+5}{16\times {{5}^{n+1}}}\]
C.	\[\frac{3}{7}-\frac{3n+5}{16\times {{5}^{n-1}}}\]
D.	\[\frac{1}{2}-\frac{5n+1}{3\times {{5}^{n+2}}}\]
Answer» B. \[\frac{3}{4}-\frac{2n+5}{16\times {{5}^{n+1}}}\]

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