 Hello and welcome to the session. In this session we discuss the following question which says, in two factories A and B engaged in the same industrial area, the average weekly wages in dollar and standard deviations are as follows, that is given in this table. First, which factory A or B pays out a larger amount as weekly wages? Second, which factory A or B has greater variability in individual wages? Before we move on to the solution, let's discuss the formula for the coefficient of variance that is Cv. This is equal to sigma upon x bar into 100. And here the sigma is the standard deviation and x bar is the arithmetic mean. This is the key idea that we use for this question. Let's proceed with the solution now. This is the table given to us in which we have the factories A and B, where are the two standard deviations and number of workers. Now in the first part we have to find out which factory A or B pays out a larger amount as weekly wages. So in the first part we have total wages paid by factory A is equal to the average weekly wages which is $25. So $25 into the number of workers in factory A that is $5,000. And so this comes out to be equal to $12500. That is total wages paid by factory A is $12500. Now in the same way let us find out the total wages paid by the factory B would be equal to the average weekly wages paid by factory B which is $25 into number of workers of factory B that is $6000. And this comes out to be equal to $150,000. So this is the total wages paid by the factory B. Now when we compare these two wages paid by the two factories A and B, we find that factory B larger amounts weekly wages. Let's see the second part. In this we have to find out which factory A or B has greater variability in individual wages. To find out this we will find out the coefficient of variance that is Cv of factory A and this would be given by sigma by the standard deviation of factory A by S bar that is the mean of factory A into 100. Now substituting the values we get this is equal to, from the table we have that 9 is the standard deviation of factory A. So 9 upon the average of factory A 25 into 100 if 4 times is 100 and 9 multiplied by 4 is 36. So we have coefficient of variance of the factory A is equal to 36. Now next we find out the coefficient of variance of the weekly wages of factory B given by Cv of B is equal to sigma B that is the standard deviation of factory B upon S bar B that is the automatic mean of the factory B into 100. Now substituting the values we get this is equal to 10 upon 25 into 100. Now 25 4 times is 100 and 4 multiplied by 10 is 40. So coefficient of variance of factory B is equal to 40. Now let us compare the coefficient of variance of factory A and coefficient of variance of factory B. We observe that the coefficient of variance of factory B is greater than factory A. Therefore we say B greater variability in individual wages. So for the second part the answer is factory B. So this complete C session we have understood the solution of this question.