作者MOTHERSB (FUCK NAVY!!)
看板GRE_Verbal
标题Re: [计量] Given two concentric circles, ...
时间Tue Feb 17 23:37:54 2009
※ 引述《IamSierra (面对转变能做什麽?)》之铭言:
: ※ 引述《sunrise5566 (想法很邪恶 行为很糟糕)》之铭言:
: : Given two concentric circles, such that
: : a tangent to the smaller circle cuts the
: : larger one at two points 'R' and 'S'.
: : If the radius of smaller circle is 2 and
: : larger circle is 5, then what is the length of segment 'RS'?
: : ANS:2 sqrt(5)
: (请自行画图)
: 连接圆心和S, R和切线形成一个等腰三角形
: 两边是5, 底边上的高是小圆的半径2
: 毕氏定理: 2*sqrt[(5^2 - 2^2)] = 2 sqrt(21)
: : If the remainder when 10^32 is divided by 11 is 'R', then
: : Col A: R+2
: : Col B: 3
: : ANS:B (我算是c = =)
: (11-1)^32 = 11n +1 , n是正整数
: 我也算相等
: : If R = Set of prime numbers from 1 to 50,
: : S = Set of multiples of 15 from 10 to 50,
: : T = Set of odd numbers from 1 to 50, then
: : how numbers will be common in all the three sets?
: : ANS: 0
: S set没有质数,R都是质数
: 答案0
: : Given numbers 1, 2, 3, 4 & 5.
: : What is the probabilty of choosing two odd numbers
: : at random from the given numbers such that
: : the sum of the two numbers must be an even number?
: 5选2有 10种
: 两奇数个加起来是偶数有
: 1, 3
: 1, 5
: 3, 5
: 所以3/10 = 30%
: : ANS: (100% 或 30% ) 好像是30 韩文太丑 看不懂
: : 以上4题 拜托各位了 <(_ _)>
第四题的要求中two odd numbers的意思是选两相异数还是奇数?
如果是奇数的话不就是100%了???
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1F:推 IamSierra :choosing two odd numbers 02/17 23:56
2F:→ IamSierra :at random 应该是随意抽 不过要是奇数 才算 02/17 23:56
3F:→ MOTHERSB :是阿 所以从中随意取两个奇数 则此两数和100%为偶 02/18 00:00
4F:→ MOTHERSB :数.... 02/18 00:00
5F:推 IamSierra :也可能抽到偶数...就不算 02/18 00:46
6F:推 purupuru :1-5随机抽两个相异的数,其中这两个是奇数的机率. 02/18 00:58
7F:→ purupuru :因为odd+odd =even...所以後面条件应该不用考虑了 02/18 00:59