Multiple choice

A bike covers a distance of 36 km at a uniform speed. Had the speed been 6 kmph less, it would have taken one hour more for the journey. The original speed of the bike was एक बाइक एक समान गति से 36 किमी की दूरी को कवर करती है। यदि गति 6 किमी प्रति घंटे कम होती, तो यात्रा के लिए एक घंटे और अधिक समय लगेगा । बाइक की मूल गति थी

  1. 16 kmph/(किमी./घंटा)

  2. 19 kmph/(किमी./घंटा)

  3. 17 kmph/(किमी./घंटा)

  4. 18 kmph/(किमी./घंटा)

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let original speed = x kmph. Time taken at x kmph = 36/x hours. At (x-6) kmph, time = 36/(x-6) hours. Difference is 1 hour: 36/(x-6) - 36/x = 1. Solving gives x=18. At 18 kmph, time is 2 hours. At 12 kmph, time is 3 hours - 1 hour more.