# Rice in Magnitudes

One day while sitting on the floor of UTA's Chemistry Research Tepee (CRT) I had a heated argument with someone over whether or not a 100 digit number qualified as a big number. I claimed that my friend couldn't even imagine a 100 digit number and he claimed that I had no idea what he could and could not imagine. I have a feeling both of those statements are true. Continuing though, I decided to make my point with rice.

How many grains of rice are in a standard 2 pound bag of rice?

The guesses were as high as 10,000 grains, and as low as only 2,000 grains. I honestly said that I'd be surprised if the number wasn't at least 50,000 grains. They decided to give me at most 10,000 grains.

Unhappy with this number, I went home and counted. Okay. Okay. I only counted out 300 grains and weighed that.

300 grains of rice = 6 grams
1 gram of rice = 50 grains
2 pounds of rice = 45,360 grains

So it turns out that we were all a bit off. I shot over by almost 5,000 grains, and they were under by about 35,000 grains. However, if you used significant figures I'd be right on. :)

What is the point of this? All the grains in a bag of rice is only 5 digits long. To take it to the next level, I then calculated the volume of this rice to be about .02604 cubic feet. So 100 digits worth of rice (10^99 minimum) would require over 5.7 x 10^92 cubic feet or approximately 3.9 x 10^81 cubic miles. To make that fit into your head a little nicer, that's 1.5 x 10^70 earth volumes.

To put that in perhaps our largest form of volume, 100 digits worth of rice would require 1.9 x 10^43 cubic light years of space.

The units still not big enough? We have but one greater thing to measure it against. The Universe. How much of the universe would be filled completely with rice if we had just 100 digits worth of rice?

135,714,285,714,280,000,000,000 Universes completely filled with rice.

Now to relate this to large number factoring of a 100 digit number. Imagine that in all that rice you are searching for two grains. It makes finding a needle in a hay stack seem trivial if you really think about it.

And, my friends, is rice in magnitudes.

(c) 2005 Nic Reveles
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