00:01
The diameters of ball bearings are distributed normally the mean diameter is 81.
00:13
So, mean diameter is 81.
00:16
Mean diameter.
00:20
Okay.
00:22
Now, the variance, variance equals to 16.
00:30
Right.
00:30
So, find the probability that the diameter is of the selected bearing is between 78 to 85 millimeters.
00:52
Millimeters.
00:55
So, round your answers to four decimal places.
01:02
Now, these are in millimeters.
01:04
Right.
01:05
So, basically mean is basically denoted by mu.
01:10
Right.
01:11
In normal distribution.
01:14
Right.
01:15
And also variance means what this means that this is this is representing sigma square.
01:21
What is sigma? sigma is a standard deviation.
01:25
Right.
01:25
So, what would be the standard deviation in sigma then that is a standard deviation.
01:32
It would be 4 that is root over 16.
01:41
Correct...