Mathematics Form one | Numbers

Base Ten Numeration

Numbers are represented by symbols called numerals. For example, numeral for the number ten is 10. Numeral for the number hundred is 100 and so on.

The symbols which represent numbers are called digits. For example the number 521 has three (3) digits which are 5, 2 and 1. There are only tendigits which are used to represent any number. These digits are 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.


2. The place value in each digit in Base ten Numeration

When we write a number, for example 521, each digit has a different value called place value. The 1 on the right means 1 ones which can be written as 1 × 1, the next number which is 2 means tens which can be written as 2 × 10 and the last number which is 5 means 5 hundreds which can be written as 5 × 100. Therefore the number 521 was found by adding the numbers 5 × 100 + 2 × 10 + 1× 1 = 521.

Note that when writing numbers in words, if there is zero between numbers we use word ‘and’

Example 1
 Write the following numbers in words:
 1. 7 008
2. 99 827 213
3. 59 000

Solutions
1. 7 008 = Seven thousand and eight.
2. 99 827 213 = Ninety nine millions eight hundred twenty seven thousand two hundred thirteen.
3. 59 000 = Fifty nine thousand.

Example 2 Write the numbers bellow in expanded form.

 1. 732
2. 1 205

. Solutions
 1. 732 = 7 x 100 + 3 x 10 + 2 x 1
 2. 1 205 = 1 x 1000 + 2 x 100 + 0 x 10 + 5 x 1


Write in numerals for each of the following:

1. 9 x 100 + 8 x 10 + 0 x 1
2. Nine hundred fifty five thousand and five.

Solutions
1. 9 x 100 + 8 x 10 + 0 x 1 = 980
2. Nine hundred fifty five thousand and five = 955 005

 Example 4 For each of the following numbers write the place value of the digit in brackets.

 1. 89 705 361 (8)
2. 57 341 (7)

Solutions
1. 8 is in the place value of ten millions.
 2. 7 is in the place value of thousands.


<<To be continued>>