Well, honestly, it depends a lot on how motivated you are. Eating well and excersizing have helped me a lot. I found a sport I liked and I practiced it everyday after school. It's VERY unhealthy to lose more than two pounds a week. You could lose a lot of weight in 3 months if you're highly motivated and active. Do anything to stay out of that kitchen too! Expect to lose no more than 60 pounds, but think of it on a weekly basis ("Okay.. this week I'll lose 1 pound"). Good luck!