The mean proportional between 36 and 9 is:

Correct option is B

Given:
The two numbers are 36 and 9.
Formula Used:
Mean Proportional = $$\sqrt {a × b}$$​​
Solution:
The two numbers are 36 and 9.
Mean Proportional = $$\sqrt {36 × 9} = \sqrt {324}$$​ = 18
Thus, the mean proportional between 36 and 9 is 18.