[" The average age of students in class "],[" X is "15.8" years.The average age of "],[" boys in class "X" is "16.4" years and that "],[" of girls is "15.4" years,What is the "],[" ratio of the number of boys and girls "],[" in class "X" ."]

The average age of students of a class is 15.8 years. The average age of boys in the class is 16.4 years and that of the girls is 15.4 years. The ratio of the number of boys to the number of girls in the class is (a) 1 : 2 (b) 2 : 3 (c) 3 : 4 (d) 3 : 5

The average age of all the students of a class is 18 years. The average age of boys of the class is 20 years and that of the girls is 15 years. If the number of girls in the class is 20, then find the number of boys in the class. (a) 15 (b) 30 (c) 45 (d) 50

The average age of all the students of a class is 22 years. The average age of boys of the class is 24 years and that of the girls is 20 years. If the number of girls in the clss is 30, then the find the number of studnets in the class.

The average age of 15 students of a class is 15 years .Out of these the average age of 5 students is 14 years and that of the other nine students is 16 years . What is the age of the 15th student ?

The average marks of 48 students in a class is 45. the average marks of the boys in the class is 40 and average marks of the girls in the class is 50. what is the ratio between the numbers of boys and the number of girls in the class ?

The average age of 12 boys is 15 years and the average age of 18 girls is 12 years .What is the conbined average age of the boys and girls ,taken together ?

The average age of r boys in a class is a years. If the average age of s of them is b years, them what is the average age of the remaining boys ?