Multiple choice

Ravi travels first 1/4th of the total distance at the speed of 10 kmph and the next 1/4th distance at the speed of 5 kmph and the last half of the distance at the speed of 10 kmph. What will be the average speed?

  1. 5.0 km/hr

  2. 8.0 km/hr

  3. 8.33 km/hr

  4. 9.0 km/hr

  5. None of these

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

Average speed is total distance divided by total time. Let total distance be D. Time = (D/4)/10 + (D/4)/5 + (D/2)/10 = D/40 + D/20 + D/20 = D/40 + 2D/40 + 2D/40 = 5D/40 = D/8. Average speed = D / (D/8) = 8 km/hr.