The Challenge: Estimate the number of marbles placed in a glass jar and then verify by counting the marbles.
Materials:
• Marbles
• Plastic jar
Procedure: Fill up the jar with marbles, to the neck and not to the brim.
Challenge criteria: Devise a method to approximate the number of marbles in the jar. Do not count the marbles. Make three estimations. Figure out the average of your estimations using the given formula:
Average = Sum of estimations / Number of estimations
Example: Suppose you make three estimations: 100, 99, and 101. As per the formula:
Average = (100+99+101)/3
= 300/3
= 100
Now, take out the marbles and count them. Cross-check your average with the counted value.