Average - General Questions

The average weight of 8 persons increases by 3 kg when a new person replaces one of them weighing 55 kg. What is the weight of the new person?

The average of 9 numbers is 42. When one more number is added, the average becomes 46. What is the new number?

The average marks of a class of 28 students is 50 and that of another class of 38 students is 66. What is the average of all the students together?

The average weight of 8 persons increases by 2.5 kg when a new person replaces one of them weighing 73 kg. What is the weight of the new person?

What is the average of the first 53 natural numbers?