Question

The 4th term of a geometric sequence is -25 and the 9th term is 25/32 find the 15th term

Answer 1

5th term is 25/2

6th term is -25/(2^2) = -25/4

7th term is 25/(2^3) = 25/8

8th term is -25/(2^4) = -25/16

9th term is 25/(2^5) = 25/32

So the 15th term is 25/(2^11) = 25/2,048