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Anjelicas Very Odd Magic Sweater

  • Classroom Resources / Problems of the Week

    Anjelicas Very Odd Magic Sweater


    PoW ID: 4052

    Problem Print

    Anjelica was wearing her new sweater when she put her hand in the pocket and found a dime. "Look, I found a dime in my pocket," she told her mom and put the dime on the table.

    She put her hand in the pocket again and this time she found three dimes.

    "Wow!" Anjelica thought, "I have a magic sweater!" She put her dimes together on the table and put her hand in her pocket again, and this time she found five!

    Her mom said, "If you do this 10 times total, you'll have 100 dimes!" Anjelica asked, "How did you do that in your head so fast?"

    What's a shortcut her mother might have used?

    Extra

    Extra: How many dimes will Anjelica find when she puts her hand in her pocket for the nth time?

    Answer Check

    Show Answer

    Anjelica's mother might have said, "I noticed that every time I looked at the table, the number of dimes was a perfect square."  

    If your answer does not match our answer, did you

    • did you make a chart?
    • did you calculate by how much the number of dimes in her pocket was increasing?
    • did you compare the number of times Anjelica reached in her pocket to the number of dimes she had on the table?
    • did you notice that the 2nd time she took dimes out and put them on the table, the number of dimes on the table was 22, or 4?
    • did you check your arithmetic?
     

    If your answer does match ours,

    • have you clearly shown and explained the work you did, so that a fellow student would understand?
    • did you show how you know your answer is right?
    • did you try the Extra?