Multiple choice general knowledge

A GIRL, A BOY, AND A DOG START WALKING DOWN A ROAD. THEY START AT THE SAME TIME, FROM THE SAME POINT, IN THE SAME DIRECTION. THE BOY WALKS AT 5 KM/H, THE GIRL AT 6KM/H. THE DOG RUNS FORM BOY TO GIRL AND BACK AGAIN WITH A CONSTANT SPEED OF 10 KM/H. THE DOG DOES NOT SLOW DOWN ON THE TURN. HOW FAR DOES THE DOG TRAVEL IN 1 HOUR?

  1. 20

  2. 100

  3. 10

  4. 30
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The dog runs continuously at 10 km/h for 1 hour, regardless of how often it turns between the boy and girl. Distance = speed × time = 10 km/h × 1 h = 10 km. The relative motion of boy and girl doesn't matter.

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