Question: what is the weight you should be at 13? 

Answer: Here is a rule of thumb.  Take your age and multiply by 7 and .....\n\nWait that's for guessing the age of an animal.  \n\nWell try it and you come up with 91 pounds.  Works for you but I should weigh 490 pounds.  Waaaaay too much.  Can you guess my age?
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