[跪求]几道很郁闷的DS.....

1. At a certain university, if 50% of the people who inquire about admission policies actually submit applications for admission, what percent of those who submit applications for admission enroll in classes at the university?

(1) 50% of those who submit applications for admission are accepted at the university.

(2) 80% of those who are accepted send a deposit to the university.

我选了A, 答案说选E. 题目不是说来询问的人之中的50%有递交申请,问递交申请的人中真正招收进来的人的比例,那知道了(1)不就可以求出了吗? 是答案错了吗?

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2. If K is a positive integer less than 10 and N=4321+K,what is the value of K?

(1) N is divisible by 3

(2) N is divisible by 7

想請教如何求數字是否含因子為7的技巧，比如3作爲因子，就是數字的每個數位相加可以被3整除。

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3。 On a certain date, Hannah invested ＄5000 at X percent simple annual interest and a different amount at Y percent simple annual interest. what amount Hannah invest at Y percent simple annual interest?

(1) the total amount of interest earned by Hannah's due investment in one year was $900

(2) Hannah invested the $5000 at 6 percent simple annual interest

我選了c, 答案是E. 是不是"what amount"要求的是具體的數值呢？

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我8月開始準備，可能問的問題很弱智……先謝謝各位解答了~

谢谢楼上解答~

也就是说第3题,问what amount 就是要我們求出一個確定的數值咯~

1题 询问的人不一定申请， 申请的人不一定就交钱（deposit），即使交了钱的人也不一定就上（enroll） 因为题目并没有给出 交了钱的跟enroll的关系 所以不能确定到底有多少人真正enroll了

1. At a certain university, if 50% of the people who inquire about admission policies actually submit applications for admission, what percent of those who submit applications for admission enroll in classes at the university?

(1) 50% of those who submit applications for admission are accepted at the university.

我還是不太明白，來詢問的有50%交了申請，問交申請的人中有多少人被招收了。條件（1）說交申請的有50%被招收了，這樣不就已經可以説明問題了嗎？

條件（2）明顯是一個與題目無關的條件。

enroll不等于be accepted

enroll 不就是be accepted嗎？

可以解釋一下中文意思嗎？

be accepted的人不一定enroll，be accepted是被录取的，enroll是be accepted中最终去入学的。

第二题有种跟简单的思路，你想想看4321加一个数被7整除，加数又在1至9之间，那么无论4321本身是否能被7整除，一定能找到一个唯一的加数使得条件成立，因为+7+7的话，肯定在10以内，且唯一

我语文学的不好，不知道有没有表达清楚