[讨论][求助]急问:OG12-DS-161 难题哦~

zbna5

各位大侠,求助啊,后天考试...OG12就这一个题_DS怎么也读不懂~不明白在说什么要考什么...大家帮帮忙,万分感谢~

161. Beginning in January of last year, Carl made deposits of $120 into his account on the 15^th of each month for several consecutive months and then made withdrawals of $50from the account on the 15^th of no other transactions in the account on the 15^th of each of the remaining months of last year. There were no other transactions in the account last year. If the closing balance of Carl’s account for May last year was $2,600, what was the range of the monthly closing balance of Carl’s account last year?

1. Last year the closing balance of Carl’s account for April was less than $2,625.

2. Last year the closing balance of Carl’s account for June was less than $2,675.

答案 C

 

[此贴子已经被作者于2009/8/25 8:02:30编辑过]

zbna5

呜呜,大家帮帮忙~~这道题是说什么的啊~~~

angelwds

就是说一个人 他在一年的前几个月里每月15号存$120 进账户里

之后从某个月开始 每月15号取 $50  一直取道年底：）

closing balance of  account

账户的期末余额

MM可以自己再试着算算 不会再问哈：）

sophiamm

这样算出来是从6月份开始每月取50得，之前都试每月存120

zbna5

哭~~~~谢谢了~~~~太感动了,你知道不,那个什么15th的...搞得我超级无比的郁闷,再次谢过!!!!!!

 

zbna5

range of the monthly closing balance 是求什么呢,为什么给了1.2 而且还得是1+2就能出结果呢?

整理一下条件:

有个xx账户

1. 1月开始连续的每月存进120

2. 某个时点(这个时间点是年内某点,不确定)开始连续的每月取出50

3. 五月账户余额2,600

问账户余额范围~

嘻嘻,谢谢大侠解答了哦~

zbna5

顶`~~~~麻烦明白的给点一下呗...这个怎么做啊~明天就考了...

zbna5

谢谢好心人啦`~

angelwds

range of the monthly closing balance

如你所说，求的是去年一年的账户余额的范围。。。应该是这样。。

对于此题，知道五月账户余额2,600

根据条件1：April was less than $2,625

可以得出  1-5月是存钱的，之后的情况不知道

因为如果1-5月是取钱的，那么账户余额应该是2650才对，与条件一相悖。。

MM可以根据这个思路继续往下做试试

lovebb4ever

答案中有两处没看明白，请教NN！！

1.“如果C在1月余额2000，前11个月连续存入120，到12月15日取出50元，which gives a range of monthly closing balance of (120)(10)。”

问题：请问这个(120)(10)代表什么意思呢，11个月连续存入120，不是应该是(120)(11）吗？

2.OG解释最后一段：given both (1)and (2), it follows from the remarks above that Carl began making $50 withdrawals on june 15.Therefore, the change to C's account balance for each month of last year are known. Since the closing balance for May is given, it follows that the closing balances for each month of last year are known, and hence the range of thease 12 known values can be determined.

问题：黄色背景部分不是很清楚。

希望哪位XDJM能瞅一眼，答疑解惑~！谢谢了！！