Final answer:
To find the geometric mean between two numbers, take the square root of their product.
Step-by-step explanation:
To find the geometric mean between two numbers, you need to take the square root of their product.
a) For the pair of numbers 8 and 81, the geometric mean is √(8 * 81) = √648 = 24.
b) For the pair of numbers 925 and 16, the geometric mean is √(925 * 16) = √14800 = 121.6.