The average marks of 45 students in a class is 40, the average of passed students is 52 and that of failed students is 52.

The average marks of 120 students are 35 . If the average of passed students was 39 and failed students was 15 , then find the number of students who have passed .

The average marks obtained by 150 students in an examination is 40. If the average marks of passed students is 60 and that of the failed students is 20, then what is the number of students who passed the examination?

The average marks obtained by 120 students in an examination is 30. If the average marks of passed students is 40 and that of the failed students is 10, what is the 25% of the number of students who passed the examination?

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 ?

3.The average age of 20 students in a class is 15 years. The average of 16 students is 12.What is the average age of remaining 4 students? A) 34, B) 45, C) 27, D) 26

The average height of 22 students of a class is 140 cm and the average height of 28 students of another class is 152 cm. What is the average height of students of both the classes?

In a class, there are 75 students and their average marks in the annual examination is 35. If the average marks of passed students is 55 and average marks of failed students is 30, then find out the number of students who failed.