※ 引述《chunning (美國夢)》之銘言：
: A hiker walking at a constant rate of 4 miles per hour is passed by a cyclist t
: raveling in the same direction along the same path at a constant rate of 20 mil
: es per hour. The cyclist stops to wait for the hiker 5 minutes after passing h
: er, while the hiker continues to walk at her constant rate. How many minutes m
: ust the cyclist wait until the hiker catches up?
: (A)
: (B) 15
: (C) 20
: (D) 25
: (E)
: 網路download的版本沒有A和E
: 答案是C 20
: 但我算的是D 25
: 可否麻煩高手指點迷津
: 感恩^^
從追過那刻開始算
c走 20m* 5/60 = 100/60
w走 4m* 5/60 = 20/60
-------------------------
差 80/60 mile
w每分鐘走 4/60mile 所以要走 (80/60)/(4/60) =20 min
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sequela
１．【醫】後遺症,後發症
２．結果
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