Place Value Through Trillions
Place value through trillions extends the base-ten number system in a repeating pattern of periods: ones, thousands, millions, billions, and trillions. In Grade 6 Saxon Math Course 1 (Chapter 2: Problem Solving with Number and Operations), students learn that each period contains three places (hundreds, tens, ones of that period) and that each place is 10 times greater than the position to its right. Commas separate periods: 2,304,567,891 has 4 periods. Students read and write large numbers in standard form, word form, and recognize that the millions period is 1,000 times larger than the thousands period.
Key Concepts
Property Our number system is based on a pattern of tens. In a place value chart, each place has a value ten times greater than the place to its right.
$$ \dots \xrightarrow{\text{trillion}} , \xrightarrow{\text{billion}} , \xrightarrow{\text{million}} , \xrightarrow{\text{thousand}} , \dots $$.
Examples In the number 384,912,657,000, the digit in the hundred millions place is 9. In the number 7,451,982, the place value of the digit 4 is hundred thousands. To write the number 3,045,891 in words, you say: three million, forty five thousand, eight hundred ninety one.
Common Questions
What are the place value periods from ones through trillions?
The periods from right to left are: ones (1), thousands (1,000), millions (1,000,000), billions (1,000,000,000), trillions (1,000,000,000,000). Each period is 1,000 times the previous.
How do commas help read large numbers?
Commas separate each group of three digits (period), making it easier to identify the period name and read the number correctly.
What is the value of the digit 4 in 4,230,000?
The 4 is in the millions place, so its value is 4 x 1,000,000 = 4,000,000.
How many times greater is the millions place than the thousands place?
1,000 times greater. Moving one period to the left multiplies the value by 1,000.
Write 3,402,050 in words.
Three million, four hundred two thousand, fifty.