00:01
Hello friend, in this question the null hypothesis is given as when mean is 11 inches while the alternate hypothesis is given as when the size of source is less than 11 inches.
00:21
In that case, first let's calculate the mean which is x bar.
00:26
It is given by summation of xi divided by the total number of observations and that is n.
00:33
So here we have sum, sum total is 129 upon 14 and from here we get the value of x bar is actually 9 .25.
00:52
Now the value of n is 14, so now we will calculate the j value.
00:56
Now the z value is given as x bar minus mu upon sigma upon root n.
01:07
So here in this question it is given that sample standard deviation is actually population standard deviation.
01:15
So we can say sample standard deviation s is actually population standard deviation sigma.
01:23
So in this case let's calculate the sample standard deviation which is given by root xi minus x bar whole square upon n minus.
01:37
So after plugging the value we get the value of sample standard deviation as around 2 .43...