Question

What is the geometric mean of 9 and 16

Answer 1

To find the geometric mean, write and solve 9/x = x/16 .

Cross multiply the proportion: x² = 144

Square root both sides: x = plus or minus 12

Answer 2

12

Explanation:

To find the geometric mean of 2 numbers, multiply them together and then take the square root

gm = sqrt(9*16)

sqrt(ab) = sqrt(a) sqrt(b)

= sqrt(9) sqrt(16)

= 3 * 4

gm = 12