- Trending Categories
- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP

- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who

# Which term of the AP: 3, 8, 13, 18, …, is 78?

Given:

Given A.P. is $3, 8, 13, 18 ……$

To do:

We have to find $78$ is which term of the given A.P.

Solution:

Let $78$ be the nth term of the given A.P.

Here,

$a_1=3, a_2=8, a_3=13$

Common difference $d=a_2-a_1=8-3=5$

We know that,

nth term $a_n=a+(n-1)d$

Therefore,

$a_{n}=3+(n-1)(5)$

$78=3+n(5)-1(5)$

$78-3=5n-5$

$75+5=5n$

$5n=80$

$n=\frac{80}{5}$

$n=16$

Hence, $78$ is the 16th term of the given A.P.

- Related Questions & Answers
- Finding n-th term of series 3, 13, 42, 108, 235... in C++
- C++ program to find Nth term of the series 0, 2, 4, 8, 12, 18…
- Program to find N-th term of series 3, 6, 18, 24, … in C++
- C++ program to find nth term of the series 5, 2, 13 41,...
- C++ program to find nth Term of the Series 1 2 2 4 4 4 4 8 8 8 8 8 8 8 8 …
- C++ program to find Nth term of the series 1, 6, 18, 40, 75, ….
- C++ program to find Nth term of the series 5, 13, 25, 41, 61…
- JavaScript code to find nth term of a series - Arithmetic Progression (AP)
- Find First element in AP which is multiple of given Prime in Python
- Find First element in AP which is multiple of given Prime in C++
- Find the nth term of the given series 0, 0, 2, 1, 4, 2, 6, 3, 8, 4… in C++
- Find the nth term of the series 0, 8, 64, 216, 512,... in C++
- Program to find N-th term of series 0, 0, 2, 1, 4, 2, 6, 3, 8…in C++
- C++ program to find Nth term of the series 1, 8, 54, 384…
- C++ Programe to find n-th term in series 1 2 2 3 3 3 4
- C++ program to find Nth term of the series 3, 14, 39, 84…

Advertisements