Answer:
45
Explanation:
a(1) = 20
a(n) = a(n - 1) x 3/2
---
start with a(2) = a(1) * (3/2) = 20* (3/2) = 30
a(3) = a(2) * (3/2) = 30 * (3/2) = 90/2 = 45
4.3m questions
5.6m answers