Question 1064928: The distance between two points And B is 100km Two cyclists start simultaneously from A to B.The speed of first cyclist is 10km/hr greater than that of the other. The first cyclist stops on his way to B and rests for50 minutes but still he is the first to arrive at B. The speed of the first cyclist is
Answer by KMST(5328)   (Show Source):
You can put this solution on YOUR website! At a speed of  kph (kilometers per hour),
the second cyclist cover  km in
 hours.
The second cyclist, at  kph,
would cover the same distance in
 hours,
but takes a break lasting  hours,
so his/her trip takes  hours.
The problem says the first cyclist trip took less time,
so  is our inequality.
Multiplying both sides of the inequality times
the positive number  , we get
Dividing by 5 both sides of the inequality, we get
You know that the quadratic polynomial
 is negative only between its zeros.
The solutions to
 <---> 
are  , and  ,
and since speeds should not be negative,
 --->  is the solution.
The second cyclist may be moving at 0 kph (sitting still),
and then the first one would be going at 10kph,
or they both may be moving,
but the first cyclist is moving at
10 kph or more, but less than 40 kph.
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