Question

insert am between 7 and 71 such that 5th am is 27. find the n.of ams

Answer 1

Here is your solution

Given
a=7
Tn=71

Now
5th term=27
a+4d=27


a+4d=27
7+4d=27
4d=27-7
4d=20
d=5

Tn=a+(n-1)d
71=7+(n-1)5
71=7+5n-5
71-7+5=5n
71-2=5n
69=5n
13.8=n

So number is 14 approx

Hope it helps