let me give it a shot!

来源: 于 2010-01-26 17:14:29 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

the second question:
1 minute guy is the fastest, who will be the one run back and forth passing the flash light. This is the key

1 and 10 cross bridge - 10 min
1 return - 1 min
1 and 5 cross bridge - 5 min
1 return - 1 min
1 and 2 cross bridge - 2 min
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19 min