SOLUTION: please help me solve this:
on a certain trip, edgar drive 231 km in exactly the same time as erwin drive 308 km. If Erwin's rate exceeded that of edgar by 13 kph. Determine the r
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on a certain trip, edgar drive 231 km in exactly the same time as erwin drive 308 km. If Erwin's rate exceeded that of edgar by 13 kph. Determine the r
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Question 844170: please help me solve this:
on a certain trip, edgar drive 231 km in exactly the same time as erwin drive 308 km. If Erwin's rate exceeded that of edgar by 13 kph. Determine the rate of Erwin Answer by algebrahouse.com(1659) (Show Source):
308
------ = Erwin's time {Erwin's rate exceeded Edgar's by 13 kph}
r + 13
231/r = 308/(r + 13) {their times were equal}
231r + 3003 = 308r {cross-multiplied in the proportion}
3003 = 77r {subtracted 231r from each side}
r = 39 {divided each side by 77}
r + 13 = 52 {substituted 39, in for r, into r + 13}
