<PRE><B>Question 1153876</B>
let speed of train be x kmh
speed of car will be x-40 kmh

t= d/s

Time taken by car - time taken by train = 1/2

120/(x-40) -120/x = 1/2 hour

Find LCD and simplify


120x -120x+(120)(40) = (1/2)x(x-40)

4800 = (1/2)(x^2-40x)

9600 = x^2-40x

x^2-40x-9600 =0

x^2-120x+80x-9600=0


(x-120)(x+80)=0


x= 120 kmph

Speed of train 120 kmph
Speed of car = 80 kmph




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