depends what excersie ur doin and how much your eating but if your 13 you shouldn't need to lose weight you should be young and fit
3x inchess
A size 36 waist typically corresponds to a waist measurement of 36 inches. To convert inches to centimeters, you can multiply by 2.54. Therefore, 36 inches is approximately 91.44 centimeters.
Your waist should be measured just above your hip bones and should be half your height in inches.
32 or 34 are good
A size 34 waist typically measures 34 inches around the waist. This size is often used in men's pants and jeans, indicating the waist circumference. It's important to note that actual fit may vary by brand and style.
32 but the hips are not
approx. 23-25 waist
The number of sit-ups that you need to do to lose two inches depends on many factors. The first is how much you weigh when you begin. The second is how long it takes to do those sit-ups. The faster you do them, the more calories you burn. Doing 100 sit-ups in 10 minutes will burn approximately 57 calories.
8 inches you can loss
You should be about 27 or 26 inches around your waist. You should also weigh about 110 pounds and be able to lift about 10 pounds.
The size charts that I have seen show a size 12 is between 25-27 in inches for the waist. Many charts neeeded additional information to produce an answer, for instance height.
Weight cannot be measured by the inches on your waist. There are too many variables to take into consideration such as sex, height, and muscular build.