Find the third proportional of 9, 7, ?, 14.

Let the missing term (third proportional in the given sequence) be x.
For the numbers 9,7,x,14 to be in proportion, the ratio of the first two numbers must equal the ratio of the last two numbers:

7
9
​
=
14
x
​

Solving for x:

x=
7
9×14
​

x=9×2=18