jr conlin's ink stained banana

This is why i don't think i'd ever get hired at Microsoft.

Why is a manhole cover round?

To fit the manhole.

How many cars are there in the USA? (A popular variant is "How many gas stations are there in the USA?")

Quite possibly more than the number of inhabitants in any given area. Evidence of this can be seen at rush hour.

How many manhole covers are there in the USA?

Sligthly more than the total number of man holes

You've got someone working for you for seven days and a gold bar to pay them. The gold bar is segmented into seven connected pieces. You must give them a piece of gold at the end of every day. If you are only allowed to make two breaks in the gold bar, how do you pay your worker?

Smelt it and divy the liquified gold into smaller ingots.

One train leaves Los Angeles at 15mph heading for New York. Another train leaves from New York at 20mph heading for Los Angeles on the same track. If a bird, flying at 25mph, leaves from Los Angeles at the same time as the train and flies back and forth between the two trains until they collide, how far will the bird have traveled?

Wait, two trains are going to collide and you're worried about the dead bird stuck between them?

Imagine a disk spinning like a record player turn table. Half of the disk is black and the other is white. Assume you have an unlimited number of color sensors. How many sensors would you have to place around the disk to determine the direction the disk is spinning? Where would they be placed?

Zero. Records spin clockwise. (Hey, you said "spinning like a record player turn table".)

Imagine an analog clock set to 12 o'clock. Note that the hour and minute hands overlap. How many times each day do both the hour and minute hands overlap? How would you determine the exact times of the day that this occurs?

Is the clock running? If yes, 21-23 times, depending on the date. If the clock isn't running, pretty much all the time.

You have two jars, 50 red marbles and 50 blue marbles. A jar will be picked at random, and then a marble will be picked from the jar. Placing all of the marbles in the jars, how can you maximize the chances of a red marble being picked? What are the exact odds of getting a red marble using your scheme?

Screw the rule and put a single red marble in both jars. Failing that, welcome to the wonderful world of 50:50.

Pairs of primes separated by a single number are called prime pairs. Examples are 17 and 19. Prove that the number between a prime pair is always divisible by 6 (assuming both numbers in the pair are greater than 6). Now prove that there are no 'prime triples.'

You know, there are these amazing machines called "computers" that are able to do detailed proofs for things like that, Granted, since i don't generally carry around things like prime number tables in my head, i'd probably use one to determine that.

There is a room with a door (closed) and three light bulbs. Outside the room there are three switches, connected to the bulbs. You may manipulate the switches as you wish, but once you open the door you can't change them. Identify each switch with its bulb.

Remove all three switches from the wall, connect all three white wires to single black wire leave in place for several minutes.. Replace switches. Of the two unmarked switches, flick one on, the other off. Open door. Identify bulbs by on, off, and still smoking. (That's the marked one.)

Suppose you had 8 billiard balls, and one of them was slightly heavier, but the only way to tell was by putting it on a scale against another. What's the fewest number of times you'd have to use the scale to find the heavier ball?

Give some kid $5 to weigh them for me. Done. i did by weighing zero billard balls. Beat that.

Imagine you are standing in front of a mirror, facing it. Raise your left hand. Raise your right hand. Look at your reflection. When you raise your left hand your reflection raises what appears to be his right hand. But when you tilt your head up, your reflection does too, and does not appear to tilt his/her head down. Why is it that the mirror appears to reverse left and right, but not up and down?

You mean aside from the properties of refraction? Because you, obviously, don't do the right sort of drugs.

You have 4 jars of pills. Each pill is a certain weight, except for contaminated pills contained in one jar, where each pill is weight + 1. How could you tell which jar had the contaminated pills in just one measurement?

Can i use that kid with the scale? He doesn't have to bring the scale, but a glass of water might help, possibly a mirror too, but that depends on what kind of "contamination" we're talking about here.

The SF Chronicle has a word game where all the letters are scrambled up and you have to figure out what the word is. Imagine that a scrambled word is 5 characters long:
1. How many possible solutions are there?
2. What if we know which 5 letters are being used?
3. Develop an algorithm to solve the word.

Are we talking about the one in English or Mandarin?
For English:
$ aspell dump master|egrep "[a-z]{5}"|wc -l
119,402, by the way. (since i doubt that the Chronicle will be running words like "xxzfg")
For Mandarin, you're on your own.

There are 4 women who want to cross a bridge. They all begin on the same side. You have 17 minutes to get all of them across to the other side. It is night. There is one flashlight. A maximum of two people can cross at one time. Any party who crosses, either 1 or 2 people, must have the flashlight with them. The flashlight must be walked back and forth, it cannot be thrown, etc. Each woman walks at a different speed. A pair must walk together at the rate of the slower woman's pace.

Woman 1: 1 minute to cross
Woman 2: 2 minutes to cross
Woman 3: 5 minutes to cross
Woman 4: 10 minutes to cross

For example if Woman 1 and Woman 4 walk across first, 10 minutes have elapsed when they get to the other side of the bridge. If Woman 4 then returns with the flashlight, a total of 20 minutes have passed and you have failed the mission. What is the order required to get all women across in 17 minutes? Now, what's the other way?

Assemble women into two groups: Woman 1 in the first group, 2, 3 and 4 in the second group. Second group get's the back seat, Woman 1 gets shotgun. We're there in around 30 seconds if i floor it.

If you had an infinite supply of water and a 5 quart and 3 quart pail, how would you measure exactly 4 quarts?

Fill 5 gallon bucket. Pour water from 5 quart into 3 stop when 3 is full. Get kid with scale. (Ok, he's either dead or tripping, but you just need the scale.) Weigh two gallon bucket. Fill 5 until scale reads double the weight.

You have a bucket of jelly beans. Some are red, some are blue, and some green. With your eyes closed, pick out 2 of a like color. How many do you have to grab to be sure you have 2 of the same?

Have that stoner kid call out the colors as you pull out the beans. Promise him the rest when the munchies kick in.

If you have two buckets, one with red paint and the other with blue paint, and you take one cup from the blue bucket and poor it into the red bucket. Then you take one cup from the red bucket and poor it into the blue bucket. Which bucket has the highest ratio between red and blue? Prove it mathematically.

You have an inordinate fascination with buckets. You know that right? By the way, since i didn't stir the buckets, i could pour the paint down the side of both buckets and draw paint from the opposite side, thereby ensuring that the mix is equal. Didn't think of that, did you Mr. Non-fluid Dynamics Type person?

TIME!
Total time coming up with those answers? 10 minutes. (A bit longer for formatting.)

Oh, and if i was asked any of those for real in an interview, i'd probably leave. i like trivia, but there's a reason it's considered trivial.