Find three geometric mean between 4/27 and 27

Answer 1

Think of this as a GP, where you want three terms between 4/27 and 27
27 = 4/27 * r^4
r^4 = 27^2 / 2^2
r = √(27/2)
Now just write the first 5 terms of the GP.

Answer 2

10 and 12