These two questions on Average is very similar. One is “include”, the other “exclude”, please advise is it the same way to work out the answer?
- The average price of a certain number of books is $9. When one more book which cost $33 is include, the average price becomes $12. Find the total number of books in the end.
2. A group of pupils took part in a quiz and scored an average of 38 marks. When one the pupils who scored 48 marks was excluded, the average marks would become 36. How many pupils took part in the quiz?