>>There is a race. Participants A and B.
>>A finishes in 29 minutes
>>B finishes in 35 minutes
>>
>>A is 6 minutes faster than B.
>>B is 6 minutes slower than B.
>>
>>Is A 17% or 21% faster than B?
>>Is B 17% or 21% slower than A?
>>
>>Title says it all, darn percentages :)
>>
>>If someone needs more than 20 minutes to finish a race, tell both of them to get their fat rear ends out of the local Burger King and into a gym! :)
>
>I think it was a (half) marathon, and not a 100m sprint :)

Not a half marathon. Maybe a 10K, and a pretty darned good time by both of them.