Three runners, Dirk, Edith, and Foley all start at the same time for a $24$ km race, and each of them runs at a constant speed. When Dirk finishes the race, Edith is $10$ km behind, and Foley is $15$ km behind. When Edith finishes the race, how far behind is Foley, in km?

jaekg Aug 30, 2024

#1**+1 **

When Dirk finishes, Edith has run 14km and Foley has run 9 km

This means that Foley runs 9/14 as fast as Edith

When Edith has run 24km, Foley has run \(24 (9/14) ≈ 15.43 km\)

So Foley is \(24 - 15.43 ≈ 8.57\) km behind!

Thanks! :)

NotThatSmart Aug 30, 2024