Question -
Answer -
Let the speed of the train = x km/hr
and time taken = y hours
Distance = speed x time = x x y = xy km
In the first case,
Speed = (x + 10) km/hr
Time = (y – 2) hours
Distance = (x + 10) (y – 2) = xy
=> xy – 2x+ 10y – 20 = xy
=> -2x + 10y – 20 = 0
=> x – 5y + 10 = 0 ……….(i)
In second case,
Speed of the train = (x – 10) km/hr
and time = (y + 3) hours
Distance = (x – 10) (y + 3) = xy
=> xy + 3x – 10y – 30 = xy
=> 3x – 10y – 30 = 0 ………(ii)
Multiplying (i) by 2 and (ii) by 1