Three runners Dave, Edith, and Foley all start at the same time for a 24 km race, and each of them runs at a constant speed. When Dave finishes the race, Edith is 8 km behind, and Foley is 12 km behind. When Edith finishes the race, how far behind is Foley, in km?
foley has run 12 km and edith has run 16 km if edith had run 1/2 of the 16.... 8km foley would have only covered 6 km
edith will run the remaining 8 km foley will still have 6 km to go .