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Chapter Sixteen - Math Activity

Elementary Math Challenge- If Hermione's three butter beers cost 6 Sickles, how much did Fred's 25 Butter Beers cost?

Middle School Math Challenge- If Harry agreed to teach defense against the dark arts only when no one had quidditch practice, and Gryffindor practices every other day, Ravenclaw practices every third day, and Hufflepuff practices every fourth day, what day would they be able to meet if they all practiced on Sunday of the same week.

Answer sheet