Puzzler of the week

[Scott MacLean]

This week's puzzler:

You have eight coins, all of which look, feel and smell identical. One of the coins is heavier than the other seven. You also have a balance scale, on which you can put coins on each side and compare their weights.

You could obviously do this with four or five weighings.

But, the question is, how can you take eight coins, and determine which is the bogus, heavier coin, with just two weighings?

Last week's puzzler:

I had had a hard day at work. The boss had been on my case. I decided to hit the local tavern on my way home.

I walked in to the tavern, and I noticed there was a ballgame on the TV that's hanging on the back wall. I took a stool at the bar, and ordered a beer. I glanced up. I'm not really that interested in baseball, but there was an attractive lady sitting there, and she seemed interested in the game. I asked her, "What's the score?"

She said, "There's no score. It's the bottom of the 5th."

There were two outs. The batter hit a hard grounder, sharply down the first-base line. Since there was no one on base, the first baseman was playing off the bag. He lunged and grabbed the ball before it could make it into the outfield.

Then�instead of running to first base to make the out�he took the ball, and fired it across the diamond to the third baseman, who caught the ball and stepped on third. The ump made the sign saying, "You're out!" All three of his team mates ran off the field.

What happened?

Last week's puzzler answer:

He wasn't watching the game on TV. He was watching the game in the mirror behind the bar.

The ball was hit to third base. The third baseman did exactly what the he should do: he scooped the ball up, dug it out of his glove, fired over to the first baseman and the first base umpire made the out sign.