大客车与小客车同时从A市出发到B市,客车每小时行驶90千米,小汽车第一小时行驶60千米,以后每小时增加5千米,小汽车需要( )小时追上客车?要算式和解释.
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大客车与小客车同时从A市出发到B市,客车每小时行驶90千米,小汽车第一小时行驶60千米,以后每小时增加5千米,小汽车需要( )小时追上客车?要算式和解释.
大客车与小客车同时从A市出发到B市,客车每小时行驶90千米,小汽车第一小时行驶60千米,以后每小时增加5千米,小汽车需要( )小时追上客车?
要算式和解释.
大客车与小客车同时从A市出发到B市,客车每小时行驶90千米,小汽车第一小时行驶60千米,以后每小时增加5千米,小汽车需要( )小时追上客车?要算式和解释.
(30/5)*2+1=13小时
解释,第一小时大客车比小汽车快30千米,因小汽车每小时增加5千米,那么到(30/5)+1=7小时时,两车速度相等,那么要再经过30/5=6小时时小客车的速度比大客车快30千米,故小汽车需要( 13 )小时追上客车
Once the third overall choose this season, candidates may McKee Lang
McGee, Washington
According to "Washington Post" reported how the recent news how the Minnesota Timberwolves signed...
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Once the third overall choose this season, candidates may McKee Lang
McGee, Washington
According to "Washington Post" reported how the recent news how the Minnesota Timberwolves signed second place with their own wish to have no. 6 Washington Wizards, and Javier - Mackey. But "Washington Post" well-known correspondent Michael - Lee has stated that the Wizards have completely no interest.
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(30/5)*2+1=13小时 解释,第一小时大客车比小汽车快30千米,因小汽车每小时增加5千米,那么到(30/5)+1=7小时时,两车速度相等,那么要再经过30/5=6小时时小客车的速度比大客车快30千米,故小汽车需要( 13 )小时追上客车
设X小时追上,此时:
客车行驶距离为:90X千米;
小客车行驶距离:60+(60+5)+(60+5*2)+。。。+(60+5*(X-1))=60X+5*(1+(X-1))/2 =60X+2.5X*(X-1)
二者距离相等,所以:90X=60X+2.5X*(X-1)
整理得:2.5(X-1)=30
解得:X=13
即,13小时后追上。...
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设X小时追上,此时:
客车行驶距离为:90X千米;
小客车行驶距离:60+(60+5)+(60+5*2)+。。。+(60+5*(X-1))=60X+5*(1+(X-1))/2 =60X+2.5X*(X-1)
二者距离相等,所以:90X=60X+2.5X*(X-1)
整理得:2.5(X-1)=30
解得:X=13
即,13小时后追上。
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13个小时
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