Brain Teasers (Starting with the Monty Hall Problem)

I didn't find it to be that simple since I'm hung on it being either a Cesuim beam Time frequency standard...or a NIST-F2 cesium-based atomic fountain clock. I'm leaning towards the former, since the NIST-F2 uses a more or less predetermined number of Cesium 133 atoms.

10-billion is a LOT of moving parts........

 

I guess I missed this one.

I guessed "They weigh the same" for both.......

 

Yeah, easy one, but i always liked this one for its obvious simplicity.

 

Here's one our principal posed, when I was in (maybe) Grade 4:

How many unique ways can you arrange 6 objects in a row?

And the answer was 6x5x4x3x2x1.

The class brain got it, nobody else came close. And that was the end of it. To this day, I wish he'd hung around, and discussed it, why that was the answer. Anyone shed light?

 

Short version . . . each time you pick an object, that removes it from the set of objects left to select from and therefore reducing the selection count down to the last one which only has one choice.

 

EDIT () - A sundial has the fewest moving parts of any timepiece that is easily accessible by anyone. Which has the most?

P.S. - I was a smartass Nuc, too...

 

An hourglass? Those have a LOT of sand grains...

 

That is for the metric system case, which was deliberately omitted from the original question.

The trick here is that there are multiple pound-ounce systems. Feathers, like nearly all common objects measured in American/Imperial units, are measured on the avoirdupois system, 16 ounces to the pound.

But gold and other precious metals are measure by Troy weight, 12 heavier ounces a lighter pound:

"Troy weight is a system of units of mass that originated in 15th-century England, and is primarily used in the precious metals industry. The Troy weights are the grain, the pennyweight (24 grains), the troy ounce (20 pennyweights), and the troy pound (12 troy ounces). The troy grain is equal to the grain-unit of the avoirdupois system, the troy ounce is heavier than the avoirdupois ounce, yet the troy pound is lighter than the avoirdupois pound." [emphasis added]

So if I had included the third case ...

... then your "they weigh the same" answer would have been correct for that case, because all the items would have been measured on the same scale. Yet another advantage of going metric.

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To add to the complexity, there are still more pound-ounce systems:

 

SCIENCE!!!

 

I guess this is why scientists AND lawyers are held in such high regard in America.....