SOLUTION: Qui-Gon Jinn can run 1 km/hr faster than Mace Windu. Qui-Gon can run 20 km in the same time that it takes Mace to run 18 km. Find the speed of each Jedi.

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Question 1127533: Qui-Gon Jinn can run 1 km/hr faster than Mace Windu. Qui-Gon can run 20 km in the same time that it takes Mace to run 18 km. Find the speed of each Jedi.
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
Let x be the speed of Mace Windu, in kilometers per hour.


Then the speed of Qui-Gon Jinn is (x+1) km/h.


The condition says


    20%2F%28x%2B1%29 = 18%2Fx.


Cross multiply:


    20*x = 18*(x+1)

    20x = 18x + 18


    20x - 18x = 18


    2x = 18  ====>  x = 18/2 = 9.


Answer.  the rates are 9 and 10 kilometers per hour.


Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


This is a problem that you can solve mentally and quickly with a very few very simple calculations, using ratios.

Qui-Gon can run 20km in the same time Mace runs 18km.
Since the times are the same, the ratio of their speeds is 20:18, or 10:9.
The problem says Qui-Gon's speed is 1km/hr faster than Mace's; the ratio of 10:9 then means that the two speeds are 10km/hr and 9km/hr.