"Malba Tahan, "The man who counted""
Is this book in English? Sounds very interesting.
"40*28 - 5 minutes = 1115 minutes = almost 20 hours." (Only in Slovenia) down here, it is nearer 19! :wink:
The manoeuvre was conducted this way:
The two boys cross to the opposite bank (10 mins)
One of them stays there while the other comes back (5 mins)
The boy gets off the boat, a soldier jumps on board and crosses the river (8 mins)
The soldier gets off, and the boat returns with the other boy (5 mins)
This operation required 28 minutes. The sequence had to be repeated as many times as the number of men in the platoon, ie 39 more times. However, it was needed to subtract 5 minutes from from the total: when the last man of the platoon crossed, the time (5 mins) taken by the second boy to cross back must not be counted, as the last soldier had already reached the other bank of the river.
The total time was therefore [(28 * 40) - 5] = 1115 minutes, which amounts to 18 hours and 35 minutes.
I would point out that it can be done faster if you leave both boys stranded on one side with the boat on the other. The first 39 soldiers cross at 28 minutes each (1092 minutes). You then have the two boys plus the last solider on one side. The final soldier then rows across himself, hence 1092 + 8 = 1100 minutes.
An Austrian mountaineer leaved Zurglatt, his village, at eight o'clock in the morning, and started his climb towards the refuge Tirpitz, on Gross Glossen mountain. He walked at a steady pace, without stopping, and his increase in heart pulse rate was negligeable. He reached the refuge at three in the afternoon, ie seven hours since he left the village. At the refuge he rested, admired the view, scribbled some notes on his diary, sang three lieder's, ate two sausages and drank a litre of beer. He then slipped in his sleeping bag and fell asleep.
The next morning, at eight o'clock, he started his descent, still with a steady pace, but faster, since he was travelling downhill. He reached Zurglatt at one in the afternoon, after walking for five hours.
Could there be a point along the path where the mountaineer walked, on the outbound and the return journey, exactly at the same time of day
You have been named as a traitor by the King, the punishment for this crime is death. Although he is a cruel tyrant he gives you one last chance at freedom. When you are finally brought before him he has this to say to you:
"There are 100 beads, 50 black and 50 white. You will be allowed to draw one bead, whilst blindfolded of course. If it is black you will be condemned to death, if it is white you will be set free".
So far so good you think to yourself, at least I have a 50/50 chance.
"The beads will be distributed amongst four boxes by me," he continued. "You must select a box by opening it, draw one bead from it and then present the bead to the court. Thus will your fate be decided".
Upon saying this a cruel smile appears on the King's face and you suddenly break into a cold sweat as you remember that the King is both very wicked and devilishly cunning.
Assuming that the King is incredibly smart, evil, thinks that you are a stupid, uneducated peasant and wants to minimise your chance of freedom, what strategy should you employ, and what is the probability of surviving
Notes:
The King whilst evil won't cheat.
The trick is to work out how he plans on distributing the beads to minimise your chance of success.
As soon as you stick your hand in one of the boxes you must draw a bead from it.
The boxes and beads light and portable, however you are not allowed to remove them from the area.
The King thinks you are stupid.
One day Arthur came to Merlin and asked him, "Show me how to be a wise and good king." Merlin replied, "If you can pass a series of mental tests, I will teach you".
Merlin then showed Arthur three chests, one was labelled GOLD COINS, the second was labelled SILVER COINS, and the last, GOLD OR SILVER COINS. He stated that all the three labels were all on the wrong chests. Given that one chest contained gold, one silver, and one bronze.
How many chests must Arthur open to deduce which label goes on which chest