00:01
So from the normal curve that we're given, we can see that it appears the mean value is about 60, and the standard deviation, or sigma, seems to be roughly 5.
00:12
So from the empirical rule, empirical rule, we have that we'd expect roughly 68 % inside of the interval between mu minus the standard deviation and mu plus the standard deviation, and we'd have that 95 % would be in the interval between mu minus, mu minus two standard deviations and mu plus two standard deviations.
00:47
So what we actually want to do here is recognize that from the 68 % part, we'd have 35 or 34 % in the interval from mu minus sigma up to zero, and we would have 95 over 2, which is, i want to say 47 .5, 95 over 2, yes, 47 .5 % have 47 .5 % in the interval from 0 up to mu plus two standard deviations.
01:24
And you have that mu minus one standard deviation is going to be 50 or 55.
01:31
And we have that the interval from 0 to mu plus two standard deviations...