World Record for the 50m dash is 5.56 in 1996
An average time for a 14-year-old running the 50 meter dash is around 9 seconds. For a 100 meter dash, it would be about 13 seconds.
12.5 seconds average time
its usually 8-9 seconds
About 30 to 34 seconds
A 12.07 time in the 100-meter dash is equivalent to 11.03 seconds in the 100-yard dash.
You could get a rough estimate by dividing by 60, and multiplying by 55. However, you can't really convert from one to the other, because the human body doesn't work that way.
A 12 year old's average time for the 100 meter dash, should be about 15 or 16 seconds.