Q. 15.0( 3 Votes )

Mark the correct A. 87

B. 88

C. 89

D. 90

Answer :

Here,a7=34 and a13=64


i.e. a+6d=34____(i) and a+12d=64_____(ii)


Subtracting (i) from (ii) we get,


(12-6)d=64-34


6d=30


d=5


Substituting d=5 in (i) we get,


a+6(5)=34


a+30=34


a=4


Now,18th term is given by a18=a+17d


=4+17×5


=89

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
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
caricature
view all courses
RELATED QUESTIONS :

There are n A.M.sRD Sharma - Mathematics

If x, y, z are inRD Sharma - Mathematics

Insert 7 A.M.s beRD Sharma - Mathematics

The 10th</suRD Sharma - Mathematics

Insert five numbeRD Sharma - Mathematics

The 4th</supRD Sharma - Mathematics

In an A.P. the fiRD Sharma - Mathematics

Insert 4 A.M.s beRD Sharma - Mathematics

Show that x2RD Sharma - Mathematics

An A.P. consists RD Sharma - Mathematics