Story Problem:
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On Monday, Colleen promises to make 48 cookies for the class Halloween goodie bags. She makes 48 cookies that first day. By Tuesday, 1/2 of the cookies are gone. Thursday morning, there are only 13 cookies let. At this rate, how many cookies will Colleen have by Friday morning? (answer: -11)
Wait! There's a moral too
Geez, I better go make some more cookies!