+0  
 
+1
1219
2
avatar+205 

 

A biker’s speed is 1.5 times faster than a walker’s speed. They start moving simultaneously in the same direction from the same point and, after 1.5 hours, the distance between them is 12.5 miles. What are their speeds?

 Nov 5, 2017
 #2
avatar+98005 
+2

Let the walker's speed in mph  = S    and the biker's speed = 1.5S

 

So

 

(1.5S - S)1.5    = 12.5

 

.5S (1.5)  = 12.5

 

.75S  = 12.5      divide both sides by .75

 

S =  12.5 / .75  = 50/3  =  16 + 2/3  mph

 

The walker's speed  = 16 + 2/3 mph      and the biker's speed  = 25 mph

 

Proof....after 1 hr the biker is    25/3 miles ahead....and after 1.5 hrs  the biker is

 

25/3  +  25 /6  =

 

[50 + 25 ]  / 6  =   75/6  =  12.5 miles ahead

 

BTW.....that walker would shred all Olympic records  !!!!!!

 

 

cool cool cool

 Nov 5, 2017
edited by CPhill  Nov 5, 2017

8 Online Users

avatar