How long on average, does it take someone to break a crack cocaine addiction in rehabilitation?

It Depends. It depends on many factors, like how long the person used the crack, how often, how much each time and if there's a family history. Also, the support system at home plays an important role. It would be , for example, nearly impossible to quit it one's spouse also used. Attending support group meetings is beneficial. One usually gets out of treatment, what one puts into treatment.
As long as it takes. There is not a magic number, every individual can be different, different level of motivation and willingness. They may have other psychological problems as well that need to be addressed. Have they had multiple relapses in the past. Are they willing to follow the recommended treatment plan regardless of time recommended. No treatment works unless at some point the person accepts it.

Related Questions

How long does it take to completely get over a crack cocaine addiction? I used for eight months and have been clean for 35 days now.

Congratulation. congratulation,you are already a winner since you took the first step toward your addiction. addiction is a tricky thing usually they tell you that you will always be vulnerable,never under estimate the power of drugs,alcohol,smoking. so you are already 35 days clean keep going into this path ,and never consider yourself immune from the drugs because you have been clean for 35 days, Read more...
Physical and mental. There is the physical dependency and the mental addiction. Congrats on 35 days. Keep that up and work on watching for the mental behaviour of addiction - seeking it, thinking of it etc. Read more...