Grade 11
题目
Grade 11
Rowing at 5 times the speed of the current,Jacob's team can travel 24km downstream in the same time it takes to travel 16km upstream.What is Jacob's team's rate and the rate of the water?
答案
if 24 and 16 mean distances,then,
let x=current speed,so,rowing speed=5x
because it takes the same time when up and down,we have:
24/(x+5x)=16/(5x-x) => 4/x=4/x
so,x can be any number,we get infinite results.
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