Question

Mean proportional between two numbers and third number is given solution

Answer 1

We will learn how to find the mean and third proportional of the set of three numbers.

If x, y and z are in continued proportion then y is called the mean proportional (or geometric mean) of x and z.

If y is the mean proportional of x and z, y^2 = xz, i.e., y = +xz−−√xz.

For example, the mean proportion of 4 and 16 = +4×16−−−−−√4×16  = +64−−√64 = 8

If x, y and z are in continued proportion then z is called the third proportional.

For example, the third proportional of 4, 8 is 16.