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Goldy's Glide SignSolution


  1. No, Ms. Forest cannot buy exactly 50 pencils at Sam's School Supply Store. She can buy 48 pencils or 51 pencils, but not 50. See the solution to 2), below.

  2. Ms. Forest could buy

    Each exchange of a package of 6 for a package of 9 increases the number of pencils by 3. So, Ms. Forest can buy any quantity counting by 3s starting at 6.

  3. One way for Ms. Forest to buy exactly 60 pencils is to get ten packages of 6.

    Trade three packages of 6 for two packages of 9, and you will find another way for Ms. Forest to buy exactly 60 pencils.

    All the ways to buy exactly 60 pencils:



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