Amotorcyclist rides for 1.5 hours at a speed of 80 km/h. then she encounters traffic and rides 20 km at an average speed of 25 km/h. what total distance did she cover?

 Total distance covered by motorcyclist in her entire journey = 140 km

Explanation:

  A motorcyclist rides for 1.5 hours at a speed of 80 km/h

  So distance covered  = Speed* time = 80*1.5 = 120 km

  Then she  encounters traffic and rides 20 km at an average speed of 25 km/h.

   So distance covered when she travels at 25 km/h = 20 km

 Total distance covered by motorcyclist = 120+20 = 140 km

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