Question

Consider the lengths of alligators to be { 18.7, 12.3, 18.6, 16.4, 15.7, 18.3, 15.8, 14.9, 17.6, 16.4, 16.7, 17.8, 16.2, 13.8, 15.2, 14.7, 13.2, 15.8, 14.6, 16.6, 16.2, 18.1, 17.5, 17.3 }. According to the Empirical Rule, 99.7% of the data should fall between what two numbers?

11.1 and 21.3

12.3 and 18.1

12.8 and 19.6

13.4 and 18.8

Answer 1

13.4 and 18.8 I believe. 

Answer 2

When dealing with normal curves
 remember the following: 68* of your data will lie within 1 s. d. of the mean; 95% within 2 s. d. , and 99.7 within 3 s. d.
z=x-u/sigma
mean is 16.2
13.4 and 18.8 I is right option
hope it helps