Q. 30

# Which term of the

Given AP is

Whose, first term, a = 20

common difference,

Let nth term of the AP be the first negative term.

Then, we have to find the least value for which

an < 0

And we know, nth term of an AP = a + (n - 1)d

Where a and d are first term and common difference respectively.

a + ( n - 1 )d < 0

-3( n - 1 ) < -80

3(n - 1) > 80

3n - 3 > 80

3n = 83

so, n will be least natural number greater than i.e.

i.e., 28th term is the first negative term of the given AP.

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Arithmetic Progression and 'nth' Term of AP55 mins
Sum of n Terms of AP56 mins
Introduction of Geometric Progression60 mins
Imp Qs Practice For Boards (AP)59 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