Level 2
There are 4 girls and 5 boys.
The average height of the 4 girls is 155 cm.
The average height of 5 boys is 164 cm.
What is the average height of all the children?
Level 3
There are 4 girls and some boys.
The total height of the children is 1440 cm.
The average height of the 4 girls is 155 cm.
The average height of the boys is 164cm.
How many boys are there?
Level 3
The average cost of some books is $75. When another 3 books are added, the total cost increases by $190. The average cost becomes $70. How many books are there in the end?
Level 3
The average cost of some books is $30.
When a book that costs $90 is added,
the average cost of the books becomes $40.
How many books are there in the end?
Level 3
The average cost of some books is $30.
When a book that costs $90 is removed,
the average cost of the books becomes $10.
How many books are there in the end?
Level 3
The average cost of some books is $30.
If 3 of the books are now each $15 more,
the average cost of the books becomes $35.
How many books are there altogether?
Level 3
The average cost of some books is $30.
If 3 of the books are now each $15 more and
2 of the books are now each $5 less,
the average cost of the books becomes $32.
How many books are there altogether?
Level 3
The average cost of some books is $10.
After 2 new books are added,
it adds another $60 to the total cost.
As a result, the average cost of all the books increases to $20.
How many books are there at first?
Level 3
The average cost of some books is $30.
After 2 new books are added,
it adds another $10 to the total cost.
As a result, the average cost of all the books decreases to $20.
How many books are there at first?
Level 1 A family's average monthly spending for August and September was $713. Their average monthly spending from October to December was $824. What was their total spending from August to December?
Level 2
A group of 50 girls and 20 boys took part in a Mathematics test. The average score of the girls was 50 points. While the average score of the boys was 64 points. What was the average score of all the students who participated in the test?