Answer:
20
Step-by-step explanation:
For two numbers, geometric mean is: [tex](x1*x2)^{\frac{1}{2}}[/tex]
We are given the numbers 10 and 40.
[tex](10*40)^{\frac{1}{2}}\\\\400^{\frac{1}{2}}\\\\\\\text{Apply Rule: } a\frac{b}{c} =\sqrt[c]{a^b}\\\\\\\sqrt{400}=\boxed{20}[/tex]
Hope this helps.
