Play the clip and ask students what they notice and wonder. Record all of their suggestions. If the question, “How many bills are in the roll?” does not come up naturally in the discussion, suggest that question as the one they will explore for this task.
There are two choices for Act 2. You may use the measurements with cubes or the measurements with the ruler and tape measure. I prefer the cubes because the dollar is slightly larger than 8 cubes. This will bring up a lot of discussion about the remaining amount after students solve the problem.
It’s not uncommon to have a range of answers to this task from 20 – 24 bills. The reason for the variation comes from different interpretations of how to handle the extra amount when people notice that one bill is slightly more than 8 cubes long. The correct answer of 22 can be seen in the video where Mike counts out the total number of bills. However, the image below the video is also helpful because it shows the end of the roll with the 3 remaining cubes. The entire money roll was measured in different colored stacks of 8 cubes. There were 22 stacks of 8 with 3 remaining cubes that covered the 22 bills.
Money Roll 3 Act Task by Mike Flynn is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
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