Question : Find the $n$th term of the following sequence: 5 + 55 + 555 + ........+$T_n$
Option 1: $5(10^n-1)$
Option 2: $5^n(10^n-1)$
Option 3: $\frac{5}{9}(10^{n} - 1)$
Option 4: $(\frac{5}{9})^{n} (10^{n} -1)$
New: SSC CHSL Tier 2 answer key released | SSC CHSL 2024 Notification PDF
Recommended: How to crack SSC CHSL | SSC CHSL exam guide
Don't Miss: Month-wise Current Affairs | Upcoming government exams
New: Unlock 10% OFF on PTE Academic. Use Code: 'C360SPL10'
Correct Answer: $\frac{5}{9}(10^{n} - 1)$
Solution : Given: 5 + 55 + 555 + ........ $n$th term = 5 (1 + 11 + 111 + ... to $n$ terms) Multiplying and divide by 9 in series, $n$th term = $\frac{5}{9}$(9 + 99 + 999 +... to $n$ terms) ⇒ $n$th term = $\frac{5}{9}$[(10–1) + (10 2 –1) +...+ $(10^{n} -1)$] ⇒ $n$th term = $\frac{5}{9}(10^{n} –1)$ Hence, the correct answer is $\frac{5}{9}(10^{n} - 1)$.
Candidates can download this e-book to give a boost to thier preparation.
Result | Eligibility | Application | Admit Card | Answer Key | Preparation Tips | Cutoff
Question : The next number of the sequence $\frac{1}{2},\frac{3}{4},\frac{5}{8},\frac{7}{16},........$ is:
Question : If $\left(3 y+\frac{3}{y}\right)=8$, then find the value of $\left(y^2+\frac{1}{y^2}\right)$.
Question : Find the fourth proportion of the numbers $\frac{1}{3}{rd}$ of 15, $\frac{4}{5}{th}$ of 25, $\frac{3}{7}{th}$ of 35:
Question : The simplified value of the following is: $\left (\frac{3}{15}a^{5}b^{6}c^{3}\times \frac{5}{9}ab^{5}c^{4} \right )\div \frac{10}{27}a^{2}bc^{3}$.
Question : Find the sum of the first five terms of the following series: $\frac{1}{1×4} + \frac{1}{4×7}+\frac{1}{7×10}+...$
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile