# Why 360?

1. Mar 27, 2006

### konartist

Does anyone know why there is 360 degrees in a circle? Why not 100 for simplicity sake?

2. Mar 27, 2006

### moose

3600 seconds in an hour.

EDIT: Maybe I should state that this is only an educated guess.... Kind of...

EDIT2: Actually, it's a complete guess.

Last edited: Mar 27, 2006
3. Mar 27, 2006

### arildno

It's a leftover from Babylonian maths, I think.

Note that 360 has a heck of a lot more divisors than 100; thus, one might argue that it is simpler to use 360 than 100 (there is, in however, a somewhat used system of measuring angles that uses 400 units in the full circle).

4. Mar 27, 2006

### FredGarvin

From here:
http://www.wonderquest.com/circle.htm

However, this source states it a bit differently: http://mathforum.org/library/drmath/view/59075.html

5. Mar 27, 2006

### Jonny_trigonometry

didn't the Babylonians use a base 60 number system?

6. Mar 27, 2006

### BobG

Sexagesimal is base 60. Actually, the Babylonians used a dual base system. Base 60 was the primary base with 10 as the secondary base (another example of a dual base system would be the Roman numeral system which has 10 as a primary base and 5 as a secondary base).

With the number of degrees approximately equal to the number of days in a year, the position of the stars shifts about 1 degree per night - a handy thing to know if you navigate by the stars as the Babylonians did.

As constructed, angles in degrees are compatible with time. The only difference is that there are 15 degrees per hour (that's the Earth's approximate rotation rate).

7. Mar 27, 2006

### heman

a similar question can be

"why are there are 32 bit operations most in computer.."

8. Mar 27, 2006

### FredGarvin

Everything in computers is based on the binary system. $$2^5 = 32$$. You also see 64 bit and 128, etc...Currently 32 bit is the norm. Soon it will progress (if things keep going the way they are).

9. Mar 27, 2006

### arildno

Due to the regular rise&fall of the Nile, it was convenient for the ancient Egyptians to make 32 bit computers in order to estimate the optimal base angle in the construction of their pyramids.

10. Mar 27, 2006

### Chi Meson

I did not know that!

11. Mar 29, 2006

### konartist

Another thing I heard was that Einstein failed math 3 times! I can't believe it.

So many interesting things about math!

12. Mar 29, 2006

### FredGarvin

What's the connection between the Nile and 32 bit? High tide - low tide?

13. Mar 29, 2006

### Integral

Staff Emeritus
I think it had more to do with the mosquito population.

14. Mar 29, 2006

### Phobos

Staff Emeritus
I seem to recall hearing that there was some spiritual significance (Babylonian?) to the number 12 too (easily divides into 360).

15. Mar 29, 2006

### RandallB

More to do with the number base (Sexagesimal is base 60) BobG was talking about. Six of those fit the year fairly well.
And a base 60 divides in so many handy ways - 2 3 4 5 6 10 12 15 20 30
Gee - think it could compete with metric?

16. Mar 29, 2006

### topsquark

Hey, using 360 degrees is FAR better than using $$2 \pi$$ radians!

-Dan

17. Mar 31, 2006

### Danger

I was totally unaware that the ancient Egyptians even had computers, never mind 32-bit ones. Did they look anything like this?

18. Mar 31, 2006

### BobG

I was always under the impression that they only had 20 bit computers.