急:问几道GRE数学1.Cars A,B and C,each traveling at its ownuniform rate,stated from the same point at the same time and raced a 400-metercourse.When A crossed the finish line,B was 40 meters behind A,and C was 58meters behind A.When B crossed th

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急:问几道GRE数学1.Cars A,B and C,each traveling at its ownuniform rate,stated from the same point at the same time and raced a 400-metercourse.When A crossed the finish line,B was 40 meters behind A,and C was 58meters behind A.When B crossed th
急:问几道GRE数学
1.Cars A,B and C,each traveling at its own
uniform rate,stated from the same point at the same time and raced a 400-meter
course.When A crossed the finish line,B was 40 meters behind A,and C was 58
meters behind A.When B crossed the finish line,how many meters was C from the
finish line?20m
解答公式(58-40)/360=x/40是什么意思?
2.Jack got an 8 percent cost of living raise
of 20 dollars per week.
翻译是杰克的工资每周增加20美元,相当于他薪水的8%.虽然知道正确翻译,可自己依然无法看懂,请帮忙分析下这个句子
3.A buzzer sounds every 15 minutes.If the
buzzer sounded at 12:40,which of the following could be a time at which the buzzer
sounded?
A.4:05 B.5:30 C.6:45 D.7:15 E.8:10
答案说会在12:40+15n时才会再响,其中n为整数,即可能响的时间为一小时中的55分、10分、25分和40分,所以选E.
4.The number of labor hours required to
produce x items is directly proportional to the square root of x.If 3 labor
hours are required to produce 20 items,how many labor hours are required to
produce 40 items?
答案是3根号下2,如何做?

急:问几道GRE数学1.Cars A,B and C,each traveling at its ownuniform rate,stated from the same point at the same time and raced a 400-metercourse.When A crossed the finish line,B was 40 meters behind A,and C was 58meters behind A.When B crossed th
1、(58-40)/360=x/40在这个公式里,x是B跑最后40米时,C比B少跑了多少米.
这个公式是这么解释的：当B跑了360米时（也就是A跑了400米时B跑的距离）,C和B的差距是58-40,那么当B跑40米时,C的差距是多少呢?前两者的比和后两者的比应该是一样的,所以列了这么一个公式.得出C在最后一段里比B差了2米,再加上他前面差的18米,等于20.能理解吧?
2、Jack got an 8 percent cost of living raise of 20 dollars per week.
如果说Jack got a raise of 20 dollars per week.可以理解吧?杰克获得了每周20美元的提升.前面的成分只是把“提升”的内容（8%的生活费增长）加进去了.综合起来就是：杰克每周的生活费增加了8%,即20美元.【至于翻译成“工资”,可能是上下文的原因,这里的生活费是指雇主提供的生活补贴】
3、每隔15分钟响一次,因为15正好是60的四分之一,所以肯定是每小时响四次,只是时间不是0,15,30,45而已,而是每个小时的10,25,40,55分（因为题目说12点40分响过一次）.由此判断,五个选项里只有8:10是在这个范围里的,所以选E.
4、生产x件产品品所需的小时数和x的平方根成固定比例.生产20件产品要3小时,生产40件产品要多少小时?列个方程就知道了,设生产40件需要的小时数为n,则
3比（20的平方根）等于n比（40的平方根）【不大会打数学公式,应该能看懂吧?】
解得n=3乘以（根号2）
【这次也都理解吗?如果不理解欢迎追问.】

（1）任何两个人的速度都是一定的。说明这两个人跑步相差的路程一定与其中某个人的跑的路程是成正比关系的。解答公式表面一开始B跑了360,BC相差58-40；现在B又跑了40，那么BC相差多少呢。
（2）杰克的工资每周增加20美元，相当于他薪水的8%。也就是说明他的工资是20/8%=250
(3)buzzer会15分钟响一次，现在呢12：40响了。显然只能在12:40的基础上...

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Cars A, B and C, each traveling at its own
uniform rate, stated from the same point at the same time and raced a 400-meter
course. When A crossed the finish line, B was 40 meters ...
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1. Cars A, B and C, each traveling at its own
  uniform rate, stated from the same point at the same time and raced a 400-meter
  course. When A crossed the finish line, B was 40 meters behind A, and C was 58
  meters behind A. When B crossed the finish line, how many meters was C from the
  finish line? 答案：20m
  解答公式(58-40)/360=x/40是什么意思?
  这题的答案是正确的，但公式中X/40应该是X/400，这样解出的X才等于20。
  思路是这样的：A跑完400公里时，B距终点40公里，就是跑了360公里，而它领先C（58-40）=18公里；那么，当B跑到终点，也就是完成400公里时，应该领先C多少呢？其实，根本不用设X，这样算更简单，也更容易理18÷360×400=20m，18÷360就是每跑1m，B领先C多少，总共是400m，那就乘上400，得出的就是400m后，B领先C的距离。
2. Jack got an 8 percent cost of living raise
  of 20 dollars per week.
  翻译是杰克的工资每周增加20美元，相当于他薪水的8%。虽然知道正确翻译，可自己依然无法看懂，请帮忙分析下这个句子
  这句话里将cost of living译为工资，我们就采用其译法。
  先把8 percent忽略，这句话就是Jack got a cost of living raise of 20 dollars per week. 意为杰克的周薪涨了20美元；如果将cost of living忽略，那么an 8 percent raise of 20 dollars per week的意思是每周增长8%，即20美元。
  现在，再来看an 8 percent cost of living raise of 20 dollars per week. 它的意思很清楚，周薪涨了8%，即20美元。
3. A buzzer sounds every 15 minutes. If the
  buzzer sounded at 12:40, which of the following could be a time at which the buzzer
  sounded?
  A.4:05 B.5:30 C.6:45 D.7:15 E.8:10
  答案E 怎么做？答案说会在12:40+15n时才会再响，其中n为整数，即可能响的时间为一小时中的55分、10分、25分和40分，所以选E。请问这句话什么意思
  答案已经说得很清楚了，因为没15分钟响一次，而每小时是60分钟，是15的整数倍，所以，每小时响的时间是固定的，即40分、55分、10分、25分这四个时点，所以，符合此条件的选项只有E。
4. The number of labor hours required to
  produce x items is directly proportional to the square root of x. If 3 labor
  hours are required to produce 20 items, how many labor hours are required to
  produce 40 items?
  答案是3根号下2，什么意思，如何做?
  The number of labor hours required to produce x items is directly proportional to the square root of x. 这句话的意思是，生产X件物品的工时与X呈平方根的正比例关系，即如果生产X件物品耗时x，那么生产2X件物品耗时为√2*x生产3X件物品耗时为√3*x。
  题目已给出生产20件物品耗时为3，那么生产40件耗时=3*√40÷20=3*√2
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急:问几道GRE数学1.Cars A,B and C,each traveling at its ownuniform rate,stated from the same point at the same time and raced a 400-metercourse.When A crossed the finish line,B was 40 meters behind A,and C was 58meters behind A.When B crossed th Gre数学. GRE数学题 a percent of b percent of c9.7 gre数学考题 a percent of b percent of c 是多少 abc/10000 几道GRE数学题1.In a series of races,10 toys cars are raced,2 cars at a time.If each car must race each of the other cars exactly twice,how many races must be held?2.The daily rate for a hotel room that sleeps 4 people is $39 for one person and x 求问几道gre数学题1.Yesturday the average number of cars per hour that passed point P was 34 between 1:00p.m.and 8:00p.m.and was x between 2:00p.m.and 7:00p.m.问x与34比较大小.这道题不是34/8-1=x/7-2么.2.a>b,c>d,a>c,问b和d的关系 these cars are different_colours A,in B,from选择?为什么? GRE数学考多久 gre数学难不难 gre数学低怎么办【GRE】数学如图 GRE数学.15题 Gre数学.22题 GRE数学怎样备考 GRE数学概念113....2/3 as many A as B:A=2/3*B ...twice as many...A as B:A=2*B 14.a if only b:b->a 13 语法上怎么理解 Tom like cars.He enjoys---model cars of all kinds.A.collects B.collecting C.to collect D.collected They worked efficiently and produced ________ those of last month.A.as twice cars as B.over twice so many cars asC.twice more cars as D.over twice as many cars as This year they have made ___ they did in 2000.A.three times as many cars as B.three times many cars asC.as many three tines cars asD.three times cars as many as GRE数学钝角锐角是否可以通过图形看出来比如题目画的是一个钝角三角形,是不是就说明一定是钝角三角形.也就是a方+b方