Ian walks 2 km to his best friend's house, then walks 0.5 km to the library. he then makes a 2.5 km walk home. the entire walk took him 3 hours. what is his average speed in km/h?

Ian's average speed in km/h = 1.66

Explanation:

  We know that average speed is the ratio of distance traveled and time taken for that distance to cover.

  In this case Ian walks 2 km to his best friend's house, then walks 0.5 km to the library. He then makes a 2.5 km walk home.

  So total distance traveled = 2+0.5+2.5 = 5 km

  Time taken for this 5 km distance travel = 3 hours

  So average speed = 5/3 =1.66 km/hour

  Ian's average speed in km/h = 1.66

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