prep模拟考试时遇到的一道题，请教。

watermoon07

A certain library assesses fines for overdue book as follows. On the 1^st day that a book is overdue, the total fine is $0.1, for each additional day that the book is overdue, the total fine is either increased by $0.3 or doubled, whichever results in the lesser amount. What is the total fine for a book on the 4^th day it is overdue?

A. $0.6     B. $0.7    C $0.8     D. $0.9    E. $1.0

the answer is B.

请问怎么出来的0.7呢？

先谢！

newniuniu

1st day: 0.1

2nd day: 0.2

3rd day: 0.4

4th day: 0.4+0.3<2*0.4===> Total fine on the 4th day is 0.7

gonghao

以下是引用newniuniu在2007-9-14 10:42:00的发言：

1st day: 0.1

2nd day: 0.2

3rd day: 0.4

4th day: 0.4+0.3<2*0.4===> Total fine on the 4th day is 0.7

这里也向newniuniu MM请教一下，

我个人对这题也有疑问

我觉的题目是说，第一天0.1

之后每过一天，要么加倍，要么+0.3

这样的话：

是不是应该这样？

              加倍      +0.3

第一天   0.1          0.1

第二天   0.2          0.4

第三天   0.4          0.7

第四天   0.8          1.0

这题我愣是选了C

==============================

newniuniu MM的做法是前面3天都是加倍，只有第4天才二选一，这是不是和题目要求有违背呢？

谢谢

watermoon07

newniuniu MM的做法是前面3天都是加倍，只有第4天才二选一，这是不是和题目要求有违背呢？

我也是这么想。不知道原来还可以交叉计算方法。

同时谢谢LS两位的答复。

[此贴子已经被作者于2007-9-14 21:56:14编辑过]

newniuniu

请注意题目中这句话: for each additional day that the book is overdue, the total fine is either increased by $0.3 or doubled, whichever results in the lesser amount.

也就是说, 每过一天, 是加倍还是乘0.3, 取决于哪个值小.

[此贴子已经被作者于2007-9-15 2:31:00编辑过]

watermoon07

以下是引用newniuniu在2007-9-15 2:30:00的发言：

请注意题目中这句话: for each additional day that the book is overdue, the total fine is either increased by $0.3 or doubled, whichever results in the lesser amount.

也就是说, 每过一天, 是加倍还是乘0.3, 取决于哪个值小.

再次感谢。这是一个很好的例子，让我记住仔细读题。牛MM脑筋很灵，佩服！

顺便问问，什么时候考呀？

gonghao

恩

大意了大意了

masaka

好阴险的题目俄。。

cookiebest

赞NICK~