Q. 115.0( 7 Votes )

# Solve: 1 + 6 + 11 + 16 + ….. + x = 148.

In the A.P.

First term = 1

Common difference = 6 – 1 = 5

Sum of terms =

148 =

148 =

296 = n (5n–3)

5n2 – 3n –296 = 0

5n2 –40n + 37n –296 = 0

5n(n–8) + 37(n–8) = 0

(n–8)(5n + 37) = 0

n = 8 or 5n = –37

As negative value of n is not possible, n = 8

x = 8th term of the series

x = 1 + (8–1)5

x = 1 + 35 = 36

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Interactive Quiz:Euclid's Division Lemma44 mins
Fundamental Theorem of Arithmetic-238 mins
Champ Quiz | Fundamental Principle Of Arithmetic41 mins
Fundamental Theorem of Arithmetic- 143 mins
Quiz | Imp Qs on Real Numbers37 mins
Euclids Division Lemma49 mins
NCERT | Imp. Qs. on Rational and Irrational Numbers44 mins
Application of Euclids Division Lemma50 mins
Relation Between LCM , HCF and Numbers46 mins
Quiz | Fun with Fundamental Theorem of Arithmetic51 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses