What is the ratio between the fourth proportional of 6, 8, 18, and the mean proportional between 3 & 27?

8:3

4th proportional P, Q, R, S

            S = \(\frac{QR}{P}\)

Mean proportional = \(\sqrt {PQ }\) of P & Q

4th proportional of 6, 8, 18, \(x\)

                     \(x\) = \(\frac{8 × 18}{6}\) = 24

Mean proportional = 3, 27

                           = \(\sqrt {3 × 27 }\) = 9

 4th proportional   :        Mean proportional

             24           :           9

               8           :          3