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A private jet flies the same distance in 7 hours that a commercial jet flies in 5 hours. If the speed of the commercial jet was 99 mph less than 2 times the speed of the

private jet, find the speed of each jet.
Answer

User Rolan
by
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1 Answer

5 votes

Answer:

  • Private jet - 165 mph
  • Commercial jet - 231 mph

Explanation:

Let the speed of the private jet is p and commercial jet is c.

Set equations

  • 7p = 5c
  • c = 2p - 99

Solve by substitution

  • 7p = 5(2p - 99)
  • 7p = 10p - 495
  • 10p - 7p = 495
  • 3p = 495
  • p = 495/3
  • p = 165

Find c:

  • c = 2*165 - 99 = 330 - 99 = 231
User Rabs G
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