From cities A and B, the distance between which is 135 km, a motorist and a cyclist drove towards each other

| August 15, 2021 | education

From cities A and B, the distance between which is 135 km, a motorist and a cyclist drove towards each other at the same time. It is known that a motorist travels 75 km more than a cyclist in an hour. Determine the speed of a cyclist if it is known that he arrived at point B on 7 hours 30 minutes later than the motorist.

Let the speed of the cyclist be x km / h, then the speed of the motorist is (x + 75) km / h.
The time spent on the way by the cyclist is 135 / x hours,
the motorist’s time is 135 / (x +75) hours.
By the condition of the problem, it is known that the travel time of a cyclist is seven and a half hours longer than the travel time of a motorist. Let’s compose and solve the equation.
135 / x – 15/2 = 135 / (x + 75)
x ^ 2 + 75x – 1350 = 0
D = 11025, quadratic roots 15 and -90.
X = 15 suits us.
Answer: the speed of the cyclist is 15 km / h.



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.