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 Question from Julie, a teacher: There are 28 students in a class. 15 have brown hair, 17 have hazel eyes, and 10 have both. How many students have neither brown hair or hazel eyes?

Hi Julie,

Have all the students stand along the wall of the classroom and draw two large circles on the floor. You are going to have some of the students stand in the circles, the students with brown hair in the brown circle, the students with hazel eyes in the blue circle. Thus the students with brown hair and hazel eyes will have to stand in both circles, the part I painted purple.

Start with the students with brown hair and hazel eyes and have then stand in the purple region. Have the rest of the students with brown hair stand in the brown region. How many are there? Have the rest of the students with hazel eyes stand in the blue region. How many are there? How many are left standing along the wall?

Penny

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