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8 tours = 3 tours + 5 tours  = 2 580 m + 4 300 m = 6 880 m

2 tours = 5 tours - 3 tours = 4 300 m - 2 580 m = 1 720 m

7 tours = 5 tours + 2 tours = 4 300 m + 1 720 m = 6 020 m

10 tours = 5 tours + 5 tours = 4 300 m + 4 300 m = 8 600 m

1 tour = 8 tours - 7 tours = 6 880 m - 6 020 m = 860 m