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UKMT Grey Kangaroo, 2017

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

A group of girls stands in a circle. Florence is the fourth on the left from Jess and the seventh on the right from Jess. How many girls are in the group?

(A) $9$ (B) $10$ (C) $11$ (D) $12$ (E) $13$

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