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2019 SAIMC keystage2-EMIC team Question 5

xIMC · 2019 SAIMC keystage2-EMIC team

Question 5

Twelve children, $A,B,C,D,E,F,G,H,I,J,K,L$, sit at a long table with chairs on each side, forming six opposite pairs. Six of them are boys and the other six are girls. The party host stipulates two rules. First, each boy must have a girl on the seat opposite him. Second, if a girl is not in a seat at either end of the table, then there must be a boy on each side of her. However, not every child observed these rules. In the diagram below, those children observing the rules are represented by white circles and those not observing the rules are represented by black circles. Since neither rule applies to a girl sitting on a seat at either end, such a girl may be represented by a white circle or a black circle. What is the gender of each child, represent a girl as “g”, a boy as “b”?

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Original response template:

Question illustration

Answer entry: give the twelve letters in the order $A,B,C,D,E,F,G,H,I,J,K,L$.