Challenge 05: International Paper
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• Download the handout for Challenge 05.
• Watch the video responses.
• Explore the follow-up challenges.
• Share your ideas in the comments section.

 

Video Responses

Spoiler Alert! Video responses include explanations of how to solve the challenge problem. We recommend that you resist the temptation to watch response videos until after you have explored the challenge individually or with a problem solving team!
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Marissa's solution.

Bronson, Dennison, Dylan, & Joe's solution.

Carter & Hunter's solution.

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Chandler, Jack, & Will's solution.

Eric, Jackson, & Joseph's solution.

Haley, Mallory, & Robin's solution.

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Mary Clare, Ryan, Sean, & Taylor's solution.

Shelby, Tasha, & Tommy's solution.

 

Follow-up Challenges

A student from Austin, Texas wondered whether it is possible to construct an "A4 rectangle" with compass and straightedge. What do you think?

None of the videos (so far!) have taken up the challenge of describing a new piece of paper for us to explore, so I'd like to encourage you to put on your problem-posing shoes!

• What if the paper had been a square? A golden rectangle?
  
• Describe a piece of paper such that exactly one-third of the paper is inside the largest circle that can be drawn. Can you find a real piece of paper that fits your description?
  
• What other questions could we pose?
  

Also: Several of the videos use so-called "cross multiplication" to solve a proportion. Explain why "cross multiplication" works!