Rayan covers a 400m bridge in 3 minutes. What is his speed?
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Answer: D. 8 kmph
Explanation
The correct answer is eight kilometers per hour for Rayan's speed. Dividing the distance of four hundred meters by three minutes gives speed in meters per minute. Converting meters per minute to kilometers per hour yields exactly eight. Speed is calculated as distance traveled divided by the time taken. Three minutes is equivalent to three-sixtieths or one-twentieth of an hour. Four hundred meters equals four-tenths of a kilometer total distance.
Kinematic calculations are essential for tracking pedestrian and vehicular travel speeds. Fitness tracking devices use distance and time data to compute average movement velocities. Transportation planning relies on accurate speed and travel time measurements. Option A represents an incorrect decimal placement during unit conversion calculations. Option B results from dividing time by distance instead of distance by time. Option C underestimates the speed by a factor of two due to conversion errors.
- Subject
- Mathematics
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- Mathematics
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- —
- Difficulty
- medium
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