The third term of a geometric progression is 9 and the fifth term is 16 find the 4th term

Answer 1

a , a r^1 , a r^2 , a r^3 , a r^4 ....... a r^(n-1)
a r^2 = 9
a r^4 = 16

a r^4 / a r^2 = 16 /9
r^2 = 16/9
r = 4/3

a r^2 = 9
a * 16/9 = 9
a = 81/16
a r^3 = fourth term = 81/16 * 64/ 27 = 3*4 = 12