00:01
Here in this question we have sample size n is equal to 9 and standard mean denoted by x bar standard mean denoted by x bar is equal to 13 .5.
00:21
The standard deviation denoted by signal is given us 3.
00:25
So the null and alternative hypothesis for the question will be the null hypothesis denoted by h0 is mu is equal to 15 .5 and the alternative hypothesis denoted by h .a.
00:44
Is mu is less than 15 .5.
00:47
This is clearly a left tamed test.
00:55
And for this test, to calculate the test statistic, we know test statistic can be calculated as z is equal to x bar minus mu over sample standard deviation, which is sigma, over square root of n.
01:15
And on substituting the values, we have its bar as 13 .5 minus mu value 15 .5 over sigma 3 over square root of 9.
01:25
Square root of 9 is anyway 3, so both 3 and 3, 1 time each.
01:29
So on calculating this, we have z is equal to minus 2 .0.
01:34
This is the value of a statistic...