Question

Please help. This question is on geometric sequences

Answer 1

13.89 to 2 dec places.

Explanation:

a7 / a5 = r^2 where r is the common ratio.

So 3/5 = r^2

r^2 = 0.6

r = +√0.6

r = 0.7746.

The first term is a5 / r^4

= 5 / (0.7746)^4

= 13.89.