 Hi and welcome to our session. Let us discuss the following question. The question says the mean of the falling frequency distribution is 57.6 and the sum of the observations is 50. Find the missing frequency F1 and F2. Now this is the distribution given to us and we have to find the missing frequency F1 and F2. Let's now begin with the solution. We will first make a table and in the first two columns we have written and given information. In the third column we will now find midpoint of each class interval and we denote midpoint by xi. A midpoint of this class interval is 10 as 0 plus 20 divided by 2 gives us 10. Then we have 20 plus 40 divided by 2 which is equal to 40. Then we have 50, 70, 90, 110. Find product of F i and xi. 7 into 10 is 70. F1 into 30 is 30 F1. 12 into 50 is 600. 20 is 725 into 110 is 550.