As a 100 yard dash sprinter in the 60's the average time would be about 10.2 to 10.3.
It is average.
The average 40 yard dash speed for an CB in the NFL is 4.25 to 4.45
Not your time... LOL
40 yard dash/10 yard dash= 4 What ever the time you got for the ten yard, you multiple it by 4. It could be an average of your running time per 10 yard dash. Sometimes for several runners, they would feel worn out by the time when reaching the 40 yard mark.