Computing time difference in hundredths of a second?

wonderingWoman: Computing time difference in hundredths of a second?
I hope Headscratcher is out there. I tried to use your formula for computing time differences in hundredths of a second for a horse endurance race. I followed your instructions, but still got the error of -999. The time cells were filled in as text as you instructed, eg: 10:59:08. Can you please help me? We have to compute these for about 30 horses and riders!

Answers and Views:

Answer by Barbados Sleeeeem!!!
use a computer.