SOLUTION: Elena bicycles 7 km/h faster than Carlos. In the same time it takes Carols to bicycle 48 km, Elena can bicycle 69 km. How fast does each bicyclist travel?

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Elena bicycles 7 km/h faster than Carlos. In the same time it takes Carols to bicycle 48 km, Elena can bicycle 69 km. How fast does each bicyclist travel?      Log On


   



Question 508075: Elena bicycles 7 km/h faster than Carlos. In the same time it takes Carols to bicycle 48 km, Elena can bicycle 69 km. How fast does each bicyclist travel?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Elena bicycles 7 km/h faster than Carlos. In the same time it takes Carlos to bicycle 48 km, Elena can bicycle 69 km. How fast does each bicyclist travel?
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Carlos DATA:
distance = 48 km ; rate = r km/hr ; time = d/r = 48/r hrs.
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Elena DATA:
distance = 69 km ; rate = r+7 km/hr ; time = d/r = 69/(r+7) hrs.
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Equation:
time = time
48/r = 69/(r+7)
48(r+7) = 69r
48r + 48*7 = 69r
21r = 48*7
r = 16 km/hr (Carlos's rate)
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r+7 = 23 km/hr (Elena's rate)
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Cheers,
Stan H.
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