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your aunt and uncle have been visiting at your home. five minutes after they drive away, you realize that they forgot their luggages you happen to know the drive slowly, so you get in your car and drive to catch up with them. Your average speed is 10 miles and hour faster that their average speed, and you catch up with them in 25 minutes. How fast did you drive.

Respuesta :

Gillruss

When you catch up, the distance traveled is the same

Distance = rate x time

r = uncle's rate

30 min = 30/60 hr = uncle's time

25 min = 25/60 hr =  your time

Uncle's distance = Your distance

(r)(30/60) = (r + 10)(25/60)

(r)(1/2) = (r + 10)(5/12)

r/2 = 5r/12 + 50/12  

6r = 5r + 50

r = 50  

Uncle's rate = 50 mph

Your rate = 50 + 10 = 60 mph

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