The mean of marks secured by 45 students in division A of class X is 69, 65 students of division B is 65 and that of 50 students of division C is 63. Find the mean of marks of the students of three divisions of Class X.
In the first 43 overs of a cricket match, the run rate was 5 runs/over. Calculate the required run rate in the remaining 7 overs to reach the target of 285 runs?
Among three numbers, the first is twice the second and thrice the third, If the average of three numbers is 517, then what is the difference between the first and the third number?
The mean of the 5 smallest numbers from a group is 15 while the mean of all the 13 members of the group taken together is 17. What is the mean of the 8 largest numbers?