I have some
Difficulty in understanding the last part of the below problem and would be very grateful if you can show me how to do it.
Thank you very much
A geometric progression has first term a (where a>0), and common ratio r.
The sum of the first n terms is Sn and the sum to infinity is S. Given that S2 is twice the value of the fifth term, find the value of r (no problem up till here. and r is found to be - 0.648)
Hence find the least value of n such that Sn is within 5% of S.
Can you provide the geometrical significance and interpretation of the last question?