There are two groups A and B of a class, consisting of 42 and 28 students respectively. If the average weight of group A is 25 kg and that of group B is 40 kg, find the average weight of the whole class. 

Average weight of 25 students of a class is 50 kg. If the weight of the class teacher is included, the average is increased by 1 kg. The weight of the teacher is 

The average age of three boys is 15 years if their ages are in the ratio 3 : 5 : 7, what will be the age of the youngest boy?

The average monthly salary of all the employees in an industry is Rs. 12,000. The average salary of male employees is Rs. 15,000 and that of female employees is Rs. 8,000. What is the ratio of male employees to female employees?

Find the average of 1.11, 0.01, 0.101, 0.001, 0.11

The average of 11 numbers is 7. If each number is doubled, what will be the new average of the numbers?

The average mathematics marks of two Sections A and B of class IX 131 the annual examination is 74. The average marks of Section A is 77.5 and that of Section B is 70. The ratios of the number of students of Section A and B is:

The average age of a husband and his wife was 27 years when the child was born, the average age of the husband, the wife and new-born child is 21 years now. The present age of the child is: