2013年新gre考试:gre数学疑难点拨
现在已经是新GRE时代了,新GRE数学难度会随第一个section的准确率而相应的提高难度,这是众所周知的事情了。那么新GRE数学疑难问题解答思路有哪些?怎样解答新GRE数学中的疑难问题呢?请看下文的解析。 1.从2 3 4 5 6 7 8 9中取数字组成三位数号码,assign to 330 employee, 数字不重复, 问多少号码unassigned? 解:P(3,8)=(8*7*6)=336 336-330=6 2.一个工作W,X做要比Y做少两天,X,Y一起做4/3W要3天,求X单独做2W要几天? 解:令W/X=x,W/Y=y,则x+2=y (1) (4/3W)/(W/x+W/y)=3 (2) 两式连立化去y,即可解得x 3.(n)=2^x3^y5^z 代表的是n的函数,x,y,z,都是positive integer, and x,y,z,分别代表n的百位,十位和个位,问如果f(m)=9f(v),m-v=? 解:因为f(m)=9f(v),所以两数百位个位都相同,令a为m的十位,b为n的十位则可知,(3^a)/(3^b)=9 解得a-b=2 所以m-v=2*10=20 4.10的n次方减38所得数的digit sum 为350. n=? 解:(... [ 查看全文 ]2013年新gre考试:gre数学疑难点拨的相关文章
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