急求100道方程题初一的快越简单越好,只限今日

急求100道方程题初一的快越简单越好,只限今日
急求100道方程题初一的
快越简单越好,只限今日

急求100道方程题初一的快越简单越好,只限今日
1.从A站经C站开往B站的一辆慢车以每小时48千米的速度行驶,当车开出24分钟后,一列执行紧急任务的快车,以每小时60千米的速度从A站驶向B站,为了使快车从A站到B站不停地行驶,慢车在距A站72千米的C站停留等候快车通过,慢车将等候多长时间?
设慢车等候时间为t,24分钟=0.4小时,方程为：
(72-48×0.4)÷48×60+60t=72
解出t=0.1小时=6分钟
2.已知一铁路桥长1000米,现有一列火车从桥上通过,测得火车从开始上桥到完全过桥共用一分钟,整列火车完全在桥上的时间为40秒,求火车的速度和长度.
1分=60秒,设火车长度为x,则火车速度可表示为(1000+x)/60和(1000-x)/40,方程为：
(1000-x)/40=(1000+x)/60
解出x=200米,火车速度=(1000+200)/60=20米/秒=72千米/小时
3.甲,乙二人分别由A,B两地沿同一条路线相向而行,在离B地12千米相遇后分别到达B,A两地,然后立即返回,在第一次相遇后6小时两人又在离A地6千米处相遇,求A,B两地的距离及甲,乙二人的速度.
设A、B两地距离为S,则第一次相遇时甲走过的距离为S-12,乙走过的距离为12；第二次相遇时甲走过的距离为S-6+12=S+6,乙走过的距离为S-12+6=S-6；这样甲的速度即为(S+6)/6,乙的速度即为(S-6)/6,第一次相遇时间为S/[(S+6)/6+(S-6)/6],可以列出方程：
(S-6)/6×S/[(S+6)/6+(S-6)/6]=12
解出S=30千米
甲的速度=(30+6)/6=6千米/小时
乙的速度=(30-6)/6=4千米/小时
4.客车与货车相向而行,客车长150米,货车长250米,客车每小时比货车快16千米,两车车头相遇到车尾离开共需10秒钟,求客车速度.
车辆尾部的相遇问题,设客车速度为v,则货车速度为v-16,10秒=1/ 360小时,方程为：
(v+v-16)×1/ 360=(150+250)/1000
解出v=80千米/小时
5.某中学有住宿生若干人,若每个房间住8人,则有3人无处住；若每个房间住9人,则有两张空床位,问该中学有宿舍多少间?住宿生多少人?
设该中学有宿舍x间,则住宿生(8x+3)人.
8x+3=9x-2
8x-9x=-2-3
x=5
8x+3=8*5+3=43
答:该中学有宿舍5间,住宿生43人.

都什么年代了，还搞题海战术，建议所有网友都别给他题，要给孩子们减负。题不在多，贵在精。

people died of various kinds of terrorist attacks (except Iraq), of which nearly half of the (9283) died in South Asia.
Frequent occurrence in the Middle East against Jews in the Palestinian terr...

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people died of various kinds of terrorist attacks (except Iraq), of which nearly half of the (9283) died in South Asia.
Frequent occurrence in the Middle East against Jews in the Palestinian terrorist attacks are against aggression and for national liberation on behalf of the typical type of terrorism, and in Russia, when the terrorist attacks in Chechnya and China's "East Turkistan" terrorist such as the type of ethnic separatist terrorism.
people died of various kinds of terrorist attacks (except Iraq), of which nearly half of the (9283) died in South Asia.
Frequent occurrence in the Middle East against Jews in the Palestinian terrorist attacks are against aggression and for national liberation on behalf of the typical type of terrorism, and in Russia, when the terrorist attacks in Chechnya and China's "East Turkistan" terrorist such as the type of ethnic separatist terrorism.
都什么年代了，还搞题海战术，建议所有网友都别给他题，要给孩子们减负。题不在多，贵在精。

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