A basic and conceptual question from arithmetic progression chapter in which we have given a series of AP 11, 8, 5, 2 and we are to find whether -150 is a term of the above series?
RS Aggarwal, Class 10, Arithmetic Progression, Chapter 23, Question no 23
D=−3
a+(n−1)d=−151$$
11+(n−1)−3=−151
11−3n+3=−151
−3n=−165
n=55
55thterm