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car moves with constant speed. from A to B, car had to arrive on time, but he ride half of the road with 2/3v speed. with what speed car has to ride the rest of the road to go on B location on time?​

User Wwnde
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1 Answer

5 votes

Answer:

  • 2v

Explanation:

Let the distance be d and average speed be v.

Half of the distance the speed was 2/3v

Let the speed be xv in the second half of the distance.

Then time is:

  • d/v = d/2 : (2/3v) + d/2 : (xv)
  • d/v = 3/4(d/v) + (1/2x)(d/v)
  • 1 = 3/4 + 1/2x
  • 1/2x = 1 - 3/4
  • 1/2x = 1/4
  • 2x = 4
  • x = 2

The rest of the road car has to ride with speed of 2v

User Chris Dworetzky
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