Pirates

I've seen this one before and haven't solved it.  Go ahead and comment answers in the blog, but not on Buzz or else  people will see them.  I quote this one from folj.com, but I've seen it before in other places as well. 

Five pirates have obtained 100 gold coins and have to divide up the loot. The pirates are all extremely intelligent, treacherous and selfish (especially the captain).

The captain always proposes a distribution of the loot. All pirates vote on the proposal, and if half the crew or more go "Aye", the loot is divided as proposed, as no pirate would be willing to take on the captain without superior force on their side.
If the captain fails to obtain support of at least half his crew (which includes himself), he faces a mutiny, and all pirates will turn against him and make him walk the plank. The pirates start over again with the next senior pirate as captain.

What is the maximum number of coins the captain can keep without risking his life?

Dots and Lines

This is a very old one, and many of you may have seen it before.  I try to avoid posting puzzles with outside-the-box solutions, but I made an exception for this one.  Using 4 straight, connected lines, connect all 9 dots.

Heads and Tails

This is borrowed from folj.com and I don't know the solution.  Submit ideas in the comments section - maybe you'll get it before I do. 

There are twenty coins sitting on the table, ten are currently heads and ten are currently tails. You are sitting at the table with a blindfold and gloves on. You are able to feel where the coins are, but are unable to see or feel if they are heads or tails. You must create two sets of coins. Each set must have the same number of heads and tails as the other group. You can only move or flip the coins, you are unable to determine their current state. How do you create two even groups of coins with the same number of heads and tails in each group?  [Note: I assume you need a guaranteed method of getting even groups, rather than method that will likely work.]

The Lantern and the Bridge

A small family is being pursued by an unknown enemy in the middle of a dark, dark night.  It comes to a deep chasm spanned by a narrow bridge. 

The family is composed of a father, mother, grandfather, and child.  The father is athletic and can cross the bridge in 1 minute; the mother can cross in 2 minutes; the child can cross in 5 minutes; and the grandfather, the slowest, takes 10 minutes to cross.  They have a lantern with them. 

Since it's pitch dark, the bridge can't be crossed without the lantern.  The bridge is so narrow that only two can cross at a time, and each pair can only move as quickly as its slowest member. 

Their pursuer is likely not far behind.  What is the quickest way to get everyone across the bridge?

Dots and Rows

This is an old one my dad told me, though I've also heard it as a CarTalk puzzler before:

Above is a straight row of 4 dots: it is a 4-dot row.
Next, we have a set of 13 dots that creates 5 different 4-dot rows.

 

Now again create 5 different 4-dot rows, but using only 10 dots.  Rows must be straight.  Oh, and before you tricksters try giving me a single long string of dots, a 5-dot row does not count as 2 4-dot rows.  You can use a dot multiple times, but rows can't overlap.

Cubic Calendar

From http://www.folj.com/puzzles/

A corporate businessman has two cubes on his office desk. Every day he arranges both cubes so that the front faces show the current day of the month.

What numbers are on the faces of the cubes to allow this?

Note: You can't represent the day "7" with a single cube with a side that says 7 on it. You have to use both cubes all the time. So the 7th day would be "07".

A Lost and Hungry Vagabond

This is from the Car Talk Puzzler:
A lost and hungry vagabond happened upon a pair of travelers one of whom had three loaves of bread while the other had five. All of the loaves were the same size and weight.

The two travelers decided to share their bread with the vagabond, and that the eight loaves should be shared equally among the three of them. When they had finished, the vagabond reached into his pocket and pulled out eight coins. He handed three coins to the traveler who had had the three loaves and five to the other one and disappeared into the inky shadows.

The next morning, right after no breakfast, the one who had received the three coins said to the other one, 'I don't think he should have given three coins to me and five to you. It's not fair.' And he was right. How should the coins have been split up?