00:01
All right, we're at question 101.
00:03
And in this question, we have two groups.
00:07
One of them is called conservative group.
00:11
I would just call it group c.
00:14
And the other group is moderate group.
00:18
So i'll just call it group m.
00:23
And in this question, our null hypothesis is pc.
00:29
Sorry, pc is equal to pm.
00:34
And our alternative hypothesis is p .c.
00:40
Does not equal to p .m.
00:44
All right.
00:48
We have the following information.
00:52
The sample size of group c is equal to 100.
00:57
And the observed proportion of group c is 0 .4.
01:03
And nm is 800 as well, p m prime is 0 .5.
01:13
So we can calculate the pool of proportion, which is nc times pc prime plus.
01:25
I'll just write the number.
01:30
So 100 times 0 .4 plus 800 times 0 .4 plus 800 times 0 .5 .5.
01:38
Over 200.
01:42
200 is just the summation of the sample size.
01:46
And we will get the number as 0 .45.
01:52
And qp prime is just 1 minus pp prime, which is 0 .55.
02:01
All right.
02:02
So we can calculate our z star.
02:06
Z star is equal to pc prime minus p m prime over square root of p p prime times q p prime times 1 p prime times 1 over n m here i'll just add the absolute value because i'm just trying to make the z star to be positive and our question does not mention, well, our question is the two -telling situation, so we will try to make the start to be positive here...