Challenge 04: Two-key Calculator
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• Download the handout for Challenge 04.
• 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.

Jameson's solution.

Solution by Andrea & Sara.

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Solution by Brett.

Solution by Ginny.

Solution by Maddie & Taylor.

 

Follow-up Challenges

• Explore Marissa's idea about the relationship between this question and the base 3 number system.
  
• How would we apply Jameson's approach if the goal was to have the calculator show the number 2000 in the end? What do you think about this approach? Does it always give us the minimum number of button presses? Why or why not?
• What advice would you give to Brett? What advice would you give to Ginny?