Question

Given the series:

$2.5+{3.5}^2+{4.5}^3+........+(n+1)5^n$

($T_n$ and $S_n$ represent the $n^{th}$ term and sum of first $n^{t}h$ term)

Calculate $\frac{S_4-S_3}{T_4}$?

• A. $2$
• B. $1$
• C. $5$
• D. None of these

Answer 1

The correct option is B $1$

We know,

$S_n-S_{n-1}=T_n$

putting n=4

$\therefore S_4-S_3=T_4$

$\Rightarrow \frac{S_4-S_3}{T_4}=1$