SOLUTION: Two boys on bicycles start from the same place and ride in opposite directions. One rides twice as fast as the other one. in 3 hours, they are 27 kilometers apart. what is the rate
Question 384773: Two boys on bicycles start from the same place and ride in opposite directions. One rides twice as fast as the other one. in 3 hours, they are 27 kilometers apart. what is the rate of speed for each boy? Found 2 solutions by stanbon, ewatrrr:Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website! Two boys on bicycles start from the same place and ride in opposite directions. One rides twice as fast as the other one. in 3 hours, they are 27 kilometers apart. what is the rate of speed for each boy?
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1st rider data:
rate = x kmh ; time = 3 hrs ; distance = 3x km
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2nd rider data:
rate = 2x kmh ; time = 3 hrs ; distance = 3(2x) = 6x km
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Equation:
distance + distance = 27 km
3x + 6x = 27
9x = 27
x = 3 km/h (1st rider's speed)
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2x = 6 km/h (2nd rider's speed)
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cheers,
Stan H.
Hi,
Let x and 2x represent their respective speeds
D = r*t
3hr*x + 3hr*2x = 27km
9hr*x = 27km
x = 3kmph
3kmph and 6kmph the speeds for the two boys.
CHECKING Our Anwser
3hr*3kmph + 3hr*6kmph = 27km