In Mathopolis, an adult is a person 21 years of age or older and a child is a person under 21 years of age.  Exactly half of the  adults in Mathopolis are female, and exactly half of the female  adults have exactly one biological child.  Nobody else has a  child, and there are no other children.  What percent of the  people of Mathopolis are children?
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<|im_start|>user
In Mathopolis, an adult is a person 21 years of age or older and a child is a person under 21 years of age.  Exactly half of the  adults in Mathopolis are female, and exactly half of the female  adults have exactly one biological child.  Nobody else has a  child, and there are no other children.  What percent of the  people of Mathopolis are children?
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user
20
In Mathopolis, an adult is a person 21 years of age or older and a child is a person under 21 years of age.  Exactly half of the  adults in Mathopolis are female, and exactly half of the female  adults have exactly one biological child.  Nobody else has a  child, and there are no other children.  What percent of the  people of Mathopolis are children?
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