+0  
 
0
2
2
avatar+683 

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?

 Jun 16, 2024
 #1
avatar+814 
-1

The answer is 14 km.

 Jun 16, 2024
 #2
avatar+1075 
+1

Let's find how far everyone ran when Dirk finished. 

When Dirk finishes, Edith has ran 14km while Foley has only ran 9km. 

 

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

 

We can now find how far Foley ran when Edith finished the race. 

Plugging in 24, we find that Foley has only ran \(24 (9/14) ≈ 15.43 km\) when Edith ran 24. 

 

This means Foley was \(24 - 15.43 ≈ 8.57\)km behind Edith. 

 

So our final answer is 8.57km. 

 

Thanks! :)

 Jun 16, 2024

3 Online Users

avatar
avatar