The average weight of 8 people is increased by 2 kg when a new person comes in place of the person who weighs 50 kg. What is the weight of the newcomer?

In a class, there are 30 girls and 15 boys and total average weight of class is $$47{7\over15}$$ kg. The total average weight of boys is 58 kg. Find the approximate average weight of girls. 

What is the average of the first five prime numbers?

Three numbers are such that the average of first two numbers is 2, the average of the last two numbers is 3 and the average of the first and the last numbers is 4, then the average of three numbers is equal to. 

The average of 5 numbers is 27. If one number is excluded, the average becomes 25. The excluded number is: 

The average monthly salary of the workers in a workshop is Rs. 8,500. If the average monthly salary of 7 technicians is Rs.10,000 and average monthly salary of the rest is Rs. 7,800, the total number of workers in the workshop is 

The average of 100 numbers is 44. The average of these 100 numbers and 4 other new numbers is 50. The average of the four new numbers will be

A man bought 13 articles at Rs. 70 each, 15 at Rs. 60 each and 12 at Rs. 65 each. The average price per article is