Re: [計量] Given two concentric circles, ...

看板GRE作者 (FUCK NAVY!!)時間17年前 (2009/02/17 23:38), 編輯推噓3(304)
留言7則, 3人參與, 最新討論串3/3 (看更多)
※ 引述《IamSierra (面對轉變能做什麼?)》之銘言: : ※ 引述《sunrise5566 (想法很邪惡 行為很糟糕)》之銘言: : : 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) : (請自行畫圖) : 連接圓心和S, R和切線形成一個等腰三角形 : 兩邊是5, 底邊上的高是小圓的半徑2 : 畢氏定理: 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是正整數 : 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沒有質數,R都是質數 : 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選2有 10種 : 兩奇數個加起來是偶數有 : 1, 3 : 1, 5 : 3, 5 : 所以3/10 = 30% : : ANS: (100% 或 30% ) 好像是30 韓文太醜 看不懂 : : 以上4題 拜託各位了 <(_ _)> 第四題的要求中two odd numbers的意思是選兩相異數還是奇數? 如果是奇數的話不就是100%了??? -- WE MBCREW!!! GOT MOTHER'S BEAT IN THE FOREVER HOUSE!!! -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 118.231.73.106

02/17 23:56, , 1F
choosing two odd numbers
02/17 23:56, 1F

02/17 23:56, , 2F
at random 應該是隨意抽 不過要是奇數 才算
02/17 23:56, 2F

02/18 00:00, , 3F
是阿 所以從中隨意取兩個奇數 則此兩數和100%為偶
02/18 00:00, 3F

02/18 00:00, , 4F
數....
02/18 00:00, 4F

02/18 00:46, , 5F
也可能抽到偶數...就不算
02/18 00:46, 5F

02/18 00:58, , 6F
1-5隨機抽兩個相異的數,其中這兩個是奇數的機率.
02/18 00:58, 6F

02/18 00:59, , 7F
因為odd+odd =even...所以後面條件應該不用考慮了
02/18 00:59, 7F
文章代碼(AID): #19cjdXdz (GRE)
文章代碼(AID): #19cjdXdz (GRE)