Have students find the averages of numbers using cubes.
To find the average of 4 and 6, student stack cubes in two
piles--one 4 high, the other 6 high. To average, the student
make the piles equal. How many are in each pile?
Do lots to practice the concept. Then try these.
1. Two numbers have a sum of 102. Their difference is
32. What are the numbers?
2. The average of five numbers is 56.
Four of the numbers are the same.
The average of one of the four numbers
and the fifth number is 80. What are the 5 numbers?
3. The sum of two number is 40.
Their difference is 14.
What are the numbers?
4. Two numbers have a sum of 72.
One number is 4 more than three times the other.
Determine the two numbers.