chandlersweigart chandlersweigart 05-05-2021 Mathematics contestada The weights of 12-year old boys are normally distributed with a mean of 89 lbs. If 68% of 12 year old boys are between the weights of 82.7 lbs and 95.3 lbs, what is the standard deviation? A 34 B 6.3 C 3.5 D 12.6