Yeah, -24 is wrong. Look down the left-most column at the rows for wind speed and find the two numbers in that row that are closest to 0°F perceived temperature. Then look at the top row and find the two actual temperatures the correspond to the two temps you found in the table. You will probably need to do linear interpolation to come up with a single number.
Here's an example. If the question is "the wind is blowing at 10 mph, approximately what temperature feels like 24°F?"
I see in the row for 10 mph the perceived temperatures that bracket 24°F, namely 27°F and 21°F. The actual temps that go with these are 35°F and 30°F. Since my perceived temperature is exactly halfway between the two values in the table, the actual temperature will be exactly halfway between 35°F and 30°F, or 32.5°F.
That's the basic idea. For the linear interpretation I think you'll need to do, you'll have to do a bit more arithmetic than I did, but it ain't "rocket science."
