Ways For Teen Girls To Lose Weight Fast?

I'm 15 and I guess you could say I'm over-weight (by like 40 pounds). I need some ways to lose weight fast because my sister said if I lose 20 pounds she will buy me an iPhone and pay the data charges. Help!

Added (1). Don't forget that I'm in highschool! So from 6-4 I'm NOT at home!

I'm sorry, but there's not really any ways to lose weight extremely fast. I would estimate that if you worked extremely hard, you could lose 20 pounds in about 3 months. This is because there are mayn ups and downs when trying to lose weight in a healthy way. What you need to do is get on a healthy, balanced diet, and do cardiovascular exercise which is any exercise that increases your heart rate substantially. This could be running/jogging, jump-roping, swimming, etc.

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First off, NEVER STOP EATING its bad for you not to eat.second just stop eating fast food and eat at home at the very least 3 times a day (breakfast, lunch, dinner) if you want to lose weight a lil faster eat every 3 hrs in small portions, that way your body won't starve and you will increase your metabolism. If you fell hungry at any point get a lil snack, because if you don't your body will go into "starvation mode" when that hapens your body will think it won't get any more food so its going to hold on to the fat you want to get rid of. And of course exercise atleast 3 times a day for at least 30 minute.

First stuff, get rid all of the junk food you have laying around the house. That means, chips, soda, candy, etc. Also, all the fattening food like french fries, bacon, chicken, etc.
Next step is, working out. Try running in the morning before school everyday for 20-30 minutes. Before running, eat a small portion of food. Like a granola bar. If you eat tons of food, you would get sick if you run if you haven't digested. Maybe do some sit ups, push ups, jumping jacks, etc.
Third step is, food. Don't miss breakfast! You would gain more because during lunch, you'd be so hungry and you would eat tons of food. Maybe in the breakfast, eat something thats 100 calories. Like a nice simple granola bar, or a cup of fruits. For lunch, you could have a cesar salad with dry chicken, and some water. For dinner, you could have anything that's not fattening!