see this notation often in mathematics.) Continuing through the second revolution and into
the third, you count
... 15, 16, 17, 20, 21, 22, ...
When you finish up the eighth revolution and enter the ninth, you count... 75, 76, 77, 100, 101, 102, ...
The hexadecimal system
Let’s invent one more strange clock. This one has sixteen hours, as shown in Fig. 1-5D. You
can see from this drawing how the base-sixteen or hexadecimal numeration system works. Use
the same upward-counting scheme as you did with the ten-hour and eight-hour clocks. There
are six new digits here, in addition to the digits in the base-ten system:
- A stands for ten
- B stands for eleven
- C stands for twelve
- D stands for thirteen
- E stands for fourteen
- F stands for fifteen
When you finish the first revolution and move into the second, place a l to the left of the
digits shown. You count
... 8, 9, A, B, C, D, E, F, 10, 11, 12, 13, ...
Continuing through the second revolution and into the third, you count
... 18, 19, 1A, 1B, 1C, 1D, 1E, 1F, 20, 21, 22, 23, ...
When you complete the tenth revolution and move into the eleventh, you count
... 98, 99, 9A, 9B, 9C, 9D, 9E, 9F, A0, A1, A2, A3, ...
It goes on like this with B, C, D, E, and F in the sixteens place. Then you get to the end of the
sixteenth revolution and move into the seventeenth, like this:
F8, F9, FA, FB, FC, FD, FE, FF, 100, 101, 102, 103, ...
Get the idea?
The Counting Base 13