Problema Solution
a train travles 140 km in the same time that a planecovers 392km. if the speed of the plane is 10 km per hour less than 3 times the speed of the train, find both speeds
Answer provided by our tutors
let
t = the time of the travel
d1 = 140 km the distance the train travels
d2 = 392km the distance the plane covers
v1 = the speed of the train
v2 = the speed of the plane
the speed of the plane is 10 km per hour less than 3 times the speed of the train
v2 = 3*v1 - 10
since speed = distance/time => time = distance/speed
d1/v1 = d2/v2
140/v1 = 392/v2
392v1 = 140v2
392v1 - 140v2 = 0 divide both sides by 28
14v1 - 5v2 = 0
by solving the system of equations
v2 = 3*v1 - 10
14v1 - 5v2 = 0
click here to see the step by step solution of the system of equations
v1 = 50 km/h
v2 = 140 km/h
the speed of the train is 50 km/h.
the speed of the plane is 140 km/h.