Question 321168
Elena bicycles 6km/h faster than Carlos. 
In the same time it takes Carlos to bicycle 27km, Elena can bicycle 45km. 
How fast does each bicyclist travel?
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Carlos DATA:
rate = x km/h ; distance = 27 km ; time = d/r = 27/x hrs
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Elena DATA:
rate = (x+6) km/h ; distance = 45 km ; rime = d/r = 45/(x+6) hrs.
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Equation:
time = time
27/x = 45/(x+6)
27x + 27*6 = 45x
18x = 27*6
x = 9 km/h (Carlos's rate)
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x+6 = 15 km/h (Elena's rate)
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Cheers,
Stan H.
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