What is the average time it takes a 25 year old woman to run a mile?

It depends ... If you're a beginning runner, then a 12 or more minute mile is somewhat average. There are many female runners who can run a mile in less than 5 minutes. Are you running for weightloss or for a personal best? If you were to take an AVERAGE of 100 female runners of any level, it would probably be between 7.5 and 9 minutes.