Martha ran 420 m, and Cole ran 60 m less than Martha. The distance Kate ran is right in the middle of Martha and Cole's distances. How far did Kate run?

390 m

Explanation:

Martha ran 420 m

Cole ran 60 m less than Martha = 420 m - 60 m = 360 m

The distance Kate ran is right in the middle of Martha and Cole's distances

Kate distance = (420 + 360) / 2 = 780 / 2 = 390 m

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