SOLUTION: A child in an airport is able to cover 339 meters in 3 minutes running at a steady speed down a moving sidewalk in the direction of the sidewalk's motion. Running at the same spe
Question 176334: A child in an airport is able to cover 339 meters in 3 minutes running at a steady speed down a moving sidewalk in the direction of the sidewalk's motion. Running at the same speed in the direction opposite to the sidewalk's movement, the child is able to cover 308 meters in 4 minutes. What is the child's running speed on a still sidewalk, and what is the speed of the moving sidewalk?
You can put this solution on YOUR website! A child in an airport is able to cover 339 meters in 3 minutes running at a steady speed down a moving sidewalk in the direction of the sidewalk's motion. Running at the same speed in the direction opposite to the sidewalk's movement, the child is able to cover 308 meters in 4 minutes. What is the child's running speed on a still sidewalk, and what is the speed of the moving sidewalk?
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Let x = child's running speed
Let y = speed of the moving walkway
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Write two distance equations (Dist = speed*time)
One for child moving with the walkway and one against the walkway
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3(x+y) = 339
4(x-y) = 308
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We can simplify both these equations divide 1st one by 3, and the 2nd one by 4
x + y = 113
x - y = 77
------------addition eliminates y, find x
2x = 190
x =
x = 95 m/min is he child's speed
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Find y using the equation x + y = 113
95 + y = 113
y = 113 - 95
y = 18 m/min speed of the walkway.
:
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Check solution in the original "against equation" 4(x-y) = 308
4(95-18) =
4 * 77 = 308; confirms our solutions
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Not that hard, right?
