也來湊個熱鬧。兩則謎語：

1. All of the paper coffee cups at my local cafe come with a tear off coupon. Every four coupons can be traded in for a free cup of coffee served in a new cup. If coffee costs $2 a cup, how many total cups of coffee can I acquire by spending $56 at my cafe and making appropiate trade-ins?

2. Four people wish to cross a long bridge in the dark of night, but the bridge will only support a maximum of two people at a time. Furthermore, the four people would take 1, 2, 5, and 10 minutes, respectively, to cross the bridge one way. If two people travel together with the flashlight, they must go at the speed of the slower person. Remember that the flashlight must be brought back across the bridge by someone each time. How can you get all four across in less than 19 minutes?

Good luck and good night!

所有跟帖： 

• 想想不應該叫謎語，可能叫謎題更準確些？免得誤導大家。 -Learntoforget- ♀ (0 bytes) () 01/26/2010 postreply 17:07:14

• let me give it a shot! -lilac09- ♀ (370 bytes) () 01/26/2010 postreply 17:14:29

• Liliac mm 好快啊！不過，題目要求用時 <19分鍾。 -Learntoforget- ♀ (0 bytes) () 01/26/2010 postreply 17:22:14

• 奇怪，小於號沒進去。“題目要求小於19分鍾” -Learntoforget- ♀ (50 bytes) () 01/26/2010 postreply 17:24:52

• 男人完了 -doitthen- ♂ (48 bytes) () 01/26/2010 postreply 17:36:46

• no, they have to cross the bridge with a flashlight. -Learntoforget- ♀ (18 bytes) () 01/26/2010 postreply 17:53:17

• ok try again! -lilac09- ♀ (231 bytes) () 01/26/2010 postreply 17:51:47

• Perfect! You got it! :) -Learntoforget- ♀ (0 bytes) () 01/26/2010 postreply 17:54:57

• 男人完了 -doitthen- ♂ (12 bytes) () 01/26/2010 postreply 17:55:14

• 美壇第一 -doitthen- ♂ (38 bytes) () 01/26/2010 postreply 18:03:17

• 那個大俠，您要讓俺死的快，就直說~~ -lilac09- ♀ (0 bytes) () 01/26/2010 postreply 18:13:39

• 感覺很爽吧 -ryu,- ♂ (0 bytes) () 01/26/2010 postreply 18:25:42

• 嗯，跟您穿著小馬甲蹦達的感覺還差一點點~~ -lilac09- ♀ (0 bytes) () 01/26/2010 postreply 18:28:31

• you are bad -doitthen- ♂ (21 bytes) () 01/26/2010 postreply 18:28:50

• Possible answers -lessisnotmore- ♀ (265 bytes) () 01/26/2010 postreply 18:00:48

• 2對，1還差一點點，就一點點。：） -Learntoforget- ♀ (0 bytes) () 01/26/2010 postreply 18:05:01

• 這一定是個GG, doitthen 同學 男人沒完~~ -lilac09- ♀ (0 bytes) () 01/26/2010 postreply 18:05:24

• must be a mm, i am sure of it -doitthen- ♂ (0 bytes) () 01/26/2010 postreply 18:06:18

• #1: 37 -ryu,- ♂ (0 bytes) () 01/26/2010 postreply 18:06:12

• Yes!37 it is. 男人確實沒完！：） -Learntoforget- ♀ (0 bytes) () 01/26/2010 postreply 18:08:54

• i hate to agree with you -doitthen- ♂ (25 bytes) () 01/26/2010 postreply 18:12:35

• 謎題已解，恭喜Liliac and Lessisnotmore同學，並感謝doitthen的積極參與！：） -Learntoforget- ♀ (0 bytes) () 01/26/2010 postreply 18:13:51

• 我又得了個榮譽獎 -doitthen- ♂ (2 bytes) () 01/26/2010 postreply 18:15:07

• 你應該還可以得個幽默獎。：） -Learntoforget- ♀ (0 bytes) () 01/26/2010 postreply 19:08:59

• 問好,謝Learntoforget撰寫的謎語,可得腦筋急轉彎. -紫君- ♀ (0 bytes) () 01/27/2010 postreply 09:51:57

• 紫君好！忘了交待，是轉載的，不是我寫的，我沒有Liliac的才氣哦。：） -learntoforget- ♀ (0 bytes) () 01/27/2010 postreply 10:49:28

• 也來看熱鬧，但我不會猜。站後排鼓掌就是了。 -yy888- ♀ (0 bytes) () 01/27/2010 postreply 21:14:44