Learn Which Term Of The Ap 3 8 13 18 Is 78

from a handpicked tutor in LIVE 1-to-1 classes

from a handpicked tutor in LIVE 1-to-1 classes

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

**Solution:**

The formula for n^{th} term of an AP is aₙ = a + (n - 1) d

The given arithmetic progression is 3, 8, 13, 18, ...

First term: a = 3

Second term: a + d = 8

Common difference: d = 8 - 3 = 5

aₙ = a + (n - 1) d

aₙ = 78, n = ?

3 + (n - 1) 5 = 78

5(n - 1) = 78 - 3

n - 1 = 15

n = 16

78 is the 16^{th} term of the given AP.

**☛ Check: **NCERT Solutions for Class 10 Maths Chapter 5

**Video Solution:**

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

NCERT Solutions Class 10 Maths Chapter 5 Exercise 5.2 Question 4

**Summary:**

78 is the 16^{th} term of the AP 3, 8, 13, 18, ...

**☛ Related Questions:**

- Find the number of terms in each of the following APs: i) 7, 13, 19,..., 205 ii) 18, 15 ½, 13 ,..., - 47.
- Check Whether -150 is a term of the AP 11, 8, 5, 2 …..
- Find the 31st term of an AP whose 11th term is 38 and the 16th term is 73.
- An AP consists of 50 terms of which the 3rd term is 12 and the last term is 106. Find the 29th term.

Math worksheets and

visual curriculum

visual curriculum