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Sheet # 190/Critical Thinking

Name: ________________________ Date_____________ 


Explain and Show Your Work

Mrs. Smith's homeroom class earned a popcorn party by completing all homework assignments for 4 weeks. It was Mrs. Smith's job to bring the popcorn, the popcorn popper, and all the other necessary supplies and utensils. When it was time for the party, the class decided they needed exactly five cups of unpopped popcorn to make the right amount of popcorn for the class. Mrs. Smith had brought a very large bag of popcorn, but she had forgotten a measuring cup. However, she did have two other containers -- one was a seven-cup container and one was a three-cup container. How could the class use these containers to measure exactly five cups of popcorn?














































Answers for Sheet # 190

Solution #1
-- Fill the three-cup container. Pour from the three into the seven-cup container. Fill the three-cup container again and pour into the seven-cup container. Fill the three-cup container again, and pour as much as possible into the seven-cup container. The seven-cup container will hold only one cup this time, which leaves two cups in the three-cup container. Pour the two cups into the popcorn popper. Fill the three-cup container again and empty that into the popcorn popper. Now there are five cups in the
popper.