CEMC Fermat, 2003

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer Canada

In the diagram, the numbers 1 to 10 are placed around a circle. Sandy crosses out 1, then 4, and then 7. Continuing in a clockwise direction, she crosses out every third number of those remaining, until only two numbers are left. The sum of these two numbers is

(A) $13$ (B) $10$ (C) $8$ (D) $14$ (E) $17$

Figure for this problem

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