Question

Which term of the ap 4 , 11 , 18 , will be 84 more than 13th term

Answer 1

⇒tn=t13 +84

⇒a+(n−1)d=(a+12d)+84

⇒(n−1)d=12d+84

⇒(n−1)7=12×7+84

⇒(n−1)7=7(12+12)

⇒n−1=24

⇒n=25

Therefore ,25th term is the required term