00:01
Hello students, by using the data given in the question, here we have to determine if this sample provides the evidence that the color distribution has changed since august 2009.
00:14
So, therefore, we can write the null hypothesis h0 as the color distribution is same as before.
00:32
That means the proportions are 24 % blue, then 13 % brown, then 16 % green, 20 % orange and 13 % red and 14 % yellow.
01:06
So that means the percentages are same as before and the alternative hypothesis that is h0 is the color distribution has changed.
01:23
Now, here to test this hypothesis, we are going to use the chi -square test and for that we need to first find the expected frequencies.
01:35
As observed frequencies we have already given to us.
01:39
So the formula for the expected frequency is expected frequency, frequency that is denoted by ei and that is equal to n into p.
01:55
Now here n is nothing but the sum of the observed frequency that is sum of the data we have given to us that is 110 plus 47 plus 52 plus 103 plus 58 plus 50 and that is equal to 420.
02:11
So n is 420 into the proportion of the respective colors.
02:17
So by using this we will get the expected frequency for the colors.
02:21
Now we have these observed frequencies that are given to us.
02:26
So to calculate the expected frequency for the first observed frequency that is for 110, this is equal to 420 into p that is proportion for the blue color that is 0 .24.
02:40
So this we will get as 100 .8.
02:45
Then similarly for the brown color it is 420 into the proportion of brown color is 0 .13...