Back to School – Friendship Math

Group Of Children Sitting On Bench In Mall

It is the first day of a new school year, and this class has only 10 students.  Ashley has 9 friends, Betty has 8, Caleb has 7, Derek has 6, Elaine has 5, Graham has 4, Henri has 3, Ivana has 2, Julie has 1.  Name one of Fred’s friends.

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friends4In a group of 4 school children, each child has exactly two friends, just one of which is their best friend. What is the minimum possible number of children for whom their best friend is also that friend’s best friend?

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It is the first day of a new school year, and this class has only 10 students.  Ashley has 9 friends, Betty has 8, Caleb has 7, Derek has 6, Elaine has 5, Graham has 4, Henri has 3, Ivana has 2, Julie has 1.  How many friends does Fred have?

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It is the first day of a new school year, and this class has only 5 students. Amy has no friends yet. Betty has one friend. Chris has three friends. Derek has two friends.  How many friends does Ellie have?

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In a group of five students, Ann has one real friend among them, Betty has two,  Craig has three, and Dianna has two. How many real friends does Edgar have in the group?

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