Level 3
Last Saturday, Jack withdrew an equal number of $10-notes and $50-notes from the bank. After spending 58 pieces of $10-notes and 10 pieces of $50-notes, the ratio of the remaining $10-notes to $50-notes became 2 : 5.
How many $10-notes had he left?
What was the total value of the notes which Jack withdrew from the bank?
Level 3
The average mass of a group of girls is 45 kg. If one more girl who weighs 75 kg joins the group, the new average mass of the group will become 48 kg. Find the total number of girls in the group.
Level 3
The average number of pages Joan read in a certain number of days was 15. In the next four days, Joan read another 88 pages. As a result, the average number of pages she read increased to 17. How many days did Joan read in total?
Level 3
The average test score of a class was 60 marks. After two students who scored an average marks of 96 marks transferred out of the class, the average score of the remaining students became 58 marks. How many students were there in the class at first?
Level 3
The average amount of money collected by a group of students at a flag day event was $125. When another 15 students turned up to help, the total amount donated increased by $1275 and the average amount of money collected became $113. How many students were there in the group at first?
