第30页

信息发布者:
$\frac{15}{4}$
解:​$(2)$​由题意,得客车经过​$600\div 60 = 10(\mathrm {h})$​到达目的地,
出租车经过​$600\div 100 = 6(\mathrm {h})$​到达目的地。
​$ $​当​$t = 2$​时,两车相距​$600 - 2×(60 + 100)=280(\mathrm {km});$​
​$ $​当​$t = 5$​时,两车相距​$5×(60 + 100)-600 = 200(\mathrm {km});$​
​$ $​当​$t = 8$​时,出租车已经到达目的地,此时两车相距​$8×60 = 480(\mathrm {km})。$​
​$ (3)$​设​$A$​加油站到甲地的距离为​$x\mathrm {km}。$​
​$ $​当​$A$​加油站比​$B$​加油站更靠近甲地时,根据题意,得​$\frac {x}{60}=\frac {600 - 200 - x}{100},$​
​$ 100x = 60×(400 - x)$​
​$ 100x = 24000 - 60x$​
​$ 100x + 60x = 24000$​
​$ 160x = 24000$​
​$ x = 150;$​
​$ $​当​$A$​加油站比​$B$​加油站更靠近乙地时,根据题意,得​$\frac {x}{60}=\frac {600 - x + 200}{100},$​
​$ 100x = 60×(800 - x)$​
​$ 100x = 48000 - 60x$​
​$ 100x + 60x = 48000$​
​$ 160x = 48000$​
​$ x = 300。$​
答:​$A$​加油站到甲地的距离为​$150\ \mathrm {km}{或3}00\ \mathrm {km}。$​