by Dan Meyer

• 1. Guess how many pennies the big circle will hold.
• 2. Write down a guess you know is too high.
• 3. Write down a guess you know is too low.

• video — the penny circles

• 4. What information would be useful to know here?

• image — the big circle's diameter

• 5. How can we use smaller circles to figure out how many pennies are in the big circle?

• file — the empty circles
• file — the full circles
• file — the full circles w/ dimensions

• video — the answer

• 6. How big is the smallest circle that would enclose 2,000 pennies?
• 7. How many pennies lie along the circumference of the big circle? Do you think that model will be quadratic also? Why or why not?

• file — the penny circumference file
• video — the penny circumference answer