Answer:
Speed of train = 60 km/hr
Speed of plane = 160 km/hr
Step-by-step explanation:
We can construct the following equations from the given information:
Speed of train * time = 150 -Equation 1
Speed of plane * time = 400 -Equation 2
Speed of plane = (3 * Speed of train) - 20 -Equation 3
We can solve these three simultaneous equations for the three variables (speed of train , speed of plane, time).
Substituting within Eq. 1 and Eq. 2 we get:
Speed of plane * 150 = 400 * Speed of train -Equation 4
Finally, solving Eq. 4 and Eq. 3 simultaneously we get:
Speed of train = 60 km/hr
Speed of plane = 160 km/hr