My Two Cents on Five Cents

A Twitter Task Gone TACKK

Kyle posted this photo on Twitter.

Questioning ensued.  I took the bait.

Questions I Explored:

• How many actual nickels would fill the Big Nickel?

• How does the value of these nickels compare to the cost to      
  actually build the Big Nickel?

Mission 1:  How do I find the area of a regular dodecagon?

Mission 2:  How do I find the volume of the Big Nickel and a regular nickel?

Mission 3:  Estimate how many nickels would fill the Big Nickel.

Mission 4:  Estimate the value of the nickels it would take to fill the Big Nickel.

Construction of the Big Nickel in 1964 cost $35,000.  

$3,189,567 ÷ $35,000 is about 91.  


This means my estimate of the number of nickels that would fill Big Nickel is worth about 91 times the cost to construct Big Nickel in 1964!


How I know my estimate is an over-estimate...

Dodecagons don't tessellate.  This fact alone means there would be gaps between small nickels when filling the Big Nickel.

Where do we go from here?

Add your work to this TACKK.

Moreover, let this resource inspire you to consider having students create a TACKK to explain their thinking on a math task!


Thank You!  Cathy