Problem: If five geometric means are inserted between 8 and 5832 , the fifth term in the geometric series is:
Answer Choices:
A. 648
B. 832
C. 1168
D. 1944
E. none of these answers.
Solution:
Denote the terms in the geometric progression by
​a1​=8,a2​=8r,⋯,a7​=8r6=5832.∴r6=729;∴r=3 and a5​=8r4=648.​