Symbols Representing Numbers

Numeration Systems

The meaning of the words numeral, numeration, base, additive, and positional are learned in the numeral system. Some of the numeral systems are the Egyptian, Roman, Babylonian, Mayan, and Hindu-Arabic. All these systems are represented by different symbols. The Web-site wichita.edu contains a lot of information about the numeral systems and their symbols along with the history of each one of them.
Printed or written symbols represent numerals, and an organized collection of numerals is called a numeration system. Base is the number of objects used in the grouping process. The Mayan and Hindu-Arabic numeration systems are positional numeration systems. In a positional numeration system, the position of each digit indicates a power of the base. The Egyptian and Roman are additive numeration systems which means that each symbol is represented as many times as needed.

Egyptian Numerals

                       1,000,000            100,000              10,000            1000              100              10                 1

"The Egyptian is an additive numeration system." (Mathematics for Elementary Teachers ).

Reading and Writing Numbers

Whole numbers from 1 to 20 have single word names. The names for the numbers 21 to 99 with the exceptions of 30, 40, 50, etc., are hyphenated names. Numbers with more than three digits are read by naming the periods.

Example:

                154,         209,          100

            Million   Thousand   Hundred

One hundred fifty four million, two hundred-nine thousand, one hundred.

Rounding Numbers

There are some rules for rounding numbers.

1.   Locate the digit with the place value to be rounded, and check the digit to the right.
2.  If the digit to the right is 5 or grater, then each digit to the right is replaced by 0 and the digit with the given value is increased by 1. 
3.  If the digit to the right is 4 or less, each digit to the right of the digit with the given place value is replace by 0.

Example:

Rounding 375,296,588 to the million, ten thousand, and thousand place values.

Million place

               375,000,000

Ten thousand place

               375,300.000

Thousand place

               375,297,000

Most of the information on this blog was taken from the text book: Mathematics for Elementary Teachers.