If the speed of a car is decreased by 12 km/h, it takes 1 hour more to cover a
distance of 240 km. Find the original speed of

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If the speed of a car is decreased by 12 km/h, it takes 1 hour more to cover a
distance of 240 km. Find the original speed of the car.​

1 thought on “If the speed of a car is decreased by 12 km/h, it takes 1 hour more to cover a<br />distance of 240 km. Find the original speed of”

  1. Answer:

    Step-by-step explanation:

    Let the speed of the car be x km per hour

    Distance = 240 km

    Speed of car = x km per hour

    Time = Distance/speed

    Time = 240/x

    If the speed of the car is decreased by 8 km per hour, it takes 1 hour more to cover a distance of 240 km

    Time during changed speed

    = 240 km /x – 8 km per hour

    240/(x – 8) – 240/x = 1 hour

    240x —240 (x – 8)/ x (x – 8) = 1 hour

    240x — 240x + 1920/ x^2 – 8x = 1 hour

    1920/x^2 – 8x = 1 hour

    Cross multiplication

    x^2 – 8x = 1920

    x^2 – 8x -1920 = 0

    x^2 – 48x + 40 x – 1920

    x (x – 48) + 40 (x – 48)

    (x + 40) (x – 48)

    x = —40 is not possible being negative hence discarded

    x = 48 km per hour

    The original speed of the car was 48 km per hour

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