Level 3
The average mass of a group of 12 children is 33 kg and the average mass of another group of 18 children is 36 kg. What is the average mass of the two groups of children?
Level 3
Bryan went on a tour with his wife and two children. An average of $799 was spent on each child while an average of $1081 was spent on each adult. On the whole, what was the average amount spent on each person for the trip?
Level 3
The average height of a group of 6 girls is 137 cm. When Kathy and Nicole joined the group, the average height increased by 4 cm. What is Kathy and Nicole's total height?
Level 3
Five numbers were written on the whiteboard as shown:
Write down the 3 numbers that will give an average of 51.
After John wrote 2 -digit number on the same whiteboard, the new average of the six numbers became a multiple of 3. What was the largest possible 2-digit number written by John?
Level 3
Five numbers were written on the whiteboard as shown:
Write down the 3 numbers that will give an average of 51.
After John wrote 2 -digit number on the same whiteboard, the new average of the six numbers became a multiple of 3. What was the largest possible 2-digit number written by John?
Level 3
The average mass of a group of girls was 37 kg. When Jamie, a girl, joined the group, the average mass of the group became 34 kg. If Jamie had a mass of 22 kg, how many girls were there in the group in the end?
Level 3
The average height of some boys is 145 cm. When 3 girls, with a total height of 393 cm, are included, the average height if the children becomes 142 cm. How many children are there altogether?
Level 3
Simon has some black and red balls. The total mass of all his balls is 242 g. He has 5 more red balls than black balls. The average mass of the black balls is 6 g. The average mass of the red balls is 10 g. How many balls does Simon have altogether?
Level 3
Kylie bought some Geography books at $17 each. She also bought an equal number of History books at a different price. The average price of one Geography and one History book was $10. Kylie paid $70 more for the Geography books than the History books.
