**3.a.3 - 2014 Q6 ****Answers**

The first term of a geometric series is 20 and the common ratio is 7/8.

The sum to infinity of the series is

(a) Find the value of

The sum to

(b) Find, to 1 decimal place, the value of

(c) Find the smallest value of

The sum to infinity of the series is

*S*_{∞} (a) Find the value of

*S*_{∞}. (2)The sum to

*N*terms of the series is*S*_{N}(b) Find, to 1 decimal place, the value of

*S*_{12}. (2)(c) Find the smallest value of

*N*, for which: (4)