[問題] 請問數學題目
In a graduating class of 236 students, 142 took algebra and 121 took chemistry.
What is the greatest number of students that could have taken both algebra and
chemistry?
A:21 B:27 C:37 D:121 E:142
答案是D 我想好久都想不出來 麻煩高手指導 謝謝
我是想 142 +121=263 263-236= 27 但是不對 哀
2. If 55 percent of a group of people have brown hair and 80 percent of the
same group do not have red hair, what fraction of those who do not have brown
hair have red hair? 答案是5/9
真的想不出來!
3 一個數學觀念: 一個圓 以直徑當成內接三角形的底 以圓上任一點畫個三角形
會因為底邊都一樣長 而造成頂角(圓上的角)度數一樣嗎??
4 N= (K+R/S)/(t/v) In the equation above K, R, S, t and v represent positive
numbers. Multiplying which one of these numbers by 2 will reduce the value of
N to 1/2 of its present value?
答案是t 不過將S變兩倍 好像也可以使N變1/2 ??
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 59.104.172.241
推
09/14 18:11, , 1F
09/14 18:11, 1F
→
09/14 18:12, , 2F
09/14 18:12, 2F
推
09/14 18:19, , 3F
09/14 18:19, 3F
→
09/14 18:19, , 4F
09/14 18:19, 4F
推
09/14 18:48, , 5F
09/14 18:48, 5F
推
09/14 18:51, , 6F
09/14 18:51, 6F
推
09/14 19:00, , 7F
09/14 19:00, 7F
→
09/14 19:00, , 8F
09/14 19:00, 8F
→
09/14 19:00, , 9F
09/14 19:00, 9F
推
09/14 19:36, , 10F
09/14 19:36, 10F
推
09/14 19:40, , 11F
09/14 19:40, 11F
→
09/14 19:42, , 12F
09/14 19:42, 12F
推
09/14 19:45, , 13F
09/14 19:45, 13F
推
09/14 19:57, , 14F
09/14 19:57, 14F
→
09/14 19:58, , 15F
09/14 19:58, 15F
推
09/14 20:11, , 16F
09/14 20:11, 16F
推
09/14 20:14, , 17F
09/14 20:14, 17F