<PRE><B>Question 893023</B>
Two runners start from the same point at the same time. They will be 4 kilometers apart at the end of two (2) hours if running in the same direction, and 16 kilometers apart at the end of one (1) hour if running in opposite directions. Find their speed.
***
let x=speed of faster runner
let y=speed of slower runner
..
running in same direction:
(x-y)*2=4
running in opposite direction:
(x+y)*1=16
..
2x-2y=4
x+y=16
..
2x-2y=4
2x+2y=32
add
4x=36
x=9
y=16-x=7
speed of faster runner=9 km/hr
speed of slower runner=7 km/hr
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