Is it possible to compute an average given a criteria.

For example, I have some data like this:

30 Day High30 Day Vol
267.22 46.11
79.24 35.29
26.24 68.58
42.39 58.24
53.94 48.04
70.70 34.96
151.13 41.55
32.77 23.85
30.87 27.88

I wanted to compute an average of ColB if ColA was equal to or greater than
75.

In this case, the average would be 40.98

Thank you in advance.