Q. 1 D5.0( 2 Votes )

Find the indicated terms in each of the following arithmetic progression:

a = 21, d = — 5; tn, t25

Answer :

Given: a = 21 , d = –5


To find: tn and t25


We have,


tn = a + (n – 1)d


tn = 21 + (n – 1)(–5)


= 21 – 5n + 5


tn = 26 – 5n


Now, n = 25


So, t25 = 21 + (25 – 1)(–5)


= 21 + 24 × (–5)


t25 = 21 – 120


t25 = –99


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Champ Quiz | Arithmetic Progression34 mins
Champ Quiz | Arithmetic Progression30 mins
Lets Check Your Knowledge in A.P.49 mins
Fundamental Theorem of Arithmetic- 143 mins
NCERT | Fundamental Theorem Of Arithmetic45 mins
Quiz on Arithmetic Progression Quiz32 mins
Arithmetic progression: Previous Year NTSE Questions34 mins
Get to Know About Geometric Progression41 mins
NCERT | Solving Questions on Introduction of A.P42 mins
Arithmetic Progression Tricks and QUIZ37 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