Base ten Numeration

When we write a number, for example 521, each digit has a different value called place value.

$521 = 5 \times 100 + 2 \times 10 + 1 \times 1$

This means:

1 is in the place value of ones: $1 \times 1$ 2 is in the place value of tens: $2 \times 10$ 5 is in the place value of hundreds: $5 \times 100$

So the value is: $521$

$7\,008 =$ Seven thousand and eight

$99\,827\,213 =$ Ninety-nine million eight hundred twenty-seven thousand two hundred thirteen

$59\,000 =$ Fifty-nine thousand

$732 = 7 \times 100 + 3 \times 10 + 2 \times 1$

$1\,205 = 1 \times 1000 + 2 \times 100 + 0 \times 10 + 5 \times 1$

$9 \times 100 + 8 \times 10 + 0 \times 1 = 980$

Nine hundred fifty-five thousand and five = $955\,005$

In $89\,705\,361$, the digit 8 is in the ten millions place.

In $57\,341$, the digit 7 is in the thousands place.

Base Ten Numeration is a system of writing numbers using ten symbols: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. It is also called the decimal system of numeration.

Consider the table below showing place values of numbers up to one billion:

If you are given numerals for a number having more than three digits, you should group the digits into groups of three from the right.

For example:

$7892939$ is written as $7\,892\,939$

When writing numbers in words, we consider their place values.

For example:

To write $725$ in words, we identify the place value of each digit:

5 is in the ones place

2 is in the tens place

7 is in the hundreds place

Therefore, the number is read as: seven hundred twenty-five.