The mean marks of boys in a class is 52 and that of girls is 42. The mean marks of boys and girls combined is 50. The percentage of boys in the class is:

The arithmetic mean of the observations 27, 69, 15, 88, 15, 54, 53, 20 and 19 is:

The arithmetic mean of the observations 35, 26, 56, 41, 56, 46, 34, 16 and 68 is:

The arithmetic mean of the observations 61, 33, 94, 48, 36, 93, 73, 94 and 53 is:

The arithmetic mean of the observations 27, 36, 12, 24, 48, 59, 60, 80 and 14 is:

The arithmetic mean of the observations 96, 70, 85, 52, 40, 88, 63, 40 and 60 is:

The mean marks of boys in a class is 52 and that of girls is 42. The mean marks of boys and girls combined is 50. The percentage of boys in the class is:

The mean of the probability distribution of the number obtained on throwing a die having 1 on three faces, 2 on two faces, and 5 on one face is:

What is the mean of the following distribution? 

The arithmetic mean of the observations 28, 31, 40, 63, 57, 37, 34, 70 and 99 is:

​Correct relation for the numbers 10, 7, 8, 5, 6, 8, 5, 8, 6 is:​