TO the nearest hundreth What is the relative
Frequency
OF students
who use only glasses
Age (years) uses
only Prescription Glasses
less than 10 13
10-13
33
14-17
38
use contact
lenses
2
6
18

He weights of 2-pound bags of best dog food are approximately normally distributed with a given mean  and standard deviation  according to the empirical rule, what percentage of the bags will have weights within 3 standard deviations of the mean? 47.5%68%95%99.7%