Two friends phil and andrew started running simultaneously from a point P in the same direction along a straight running track. The ratio of speeds of phil and andrew was 2:5. Two hours later, andrew turned back and started running running backwards at one-fifth of his original speed. He met phil at a distance of 10 km from the point P. what was phil's running speed ? Pick one
A) 1.25 km/hr	B) 2.25 km/hr	C) 2.5 km/hr	D) 3.75 km/hr	E) 6.25 km/hr
let speed of Phil was 2x and that of Andrew was 5x.   They move in same direction. relative speed = 3x.   In two hours distance between two = 3x * 2 = 6x.   Now Andrew turns back. His speed is now x.   Now both runners will have a relative speed : 2x+x 3  * 2= 
<gadget id="calculator">3  * 2</gadget>
<output>6</output>
6x.   Now Andrew turns back. His speed is now x.   Now both runners will have a relative speed : 2x+x= 3x.   The two runners will meet, when the distance between them = 6x is exhausted.   this will be done in 2 hours.   Now in initial 2 hours + these 2 hours Phil ran:   2x * 4 hours = 8x distance   8x  2  * 4= 
<gadget id="calculator"> 2  * 4</gadget>
<output>8</output>
8x distance   8x= 10   x = 10/8 = 1.25.   Phil's speed = 2x = 2.5.   2.5 km/hr is the answer.
<result>C</result>
Two friends phil and andrew started running simultaneously from a point P in the same direction along a straight running track. The ratio of speeds of phil and andrew was 2:5. Two hours later, andrew turned back and started running running backwards at one-fifth of his original speed. He met phil at a distance of 10 km from the point P. what was phil's running speed ?