Whole-Number Place Values
Whole-number place values in Grade 4 extend to seven, eight, and nine digits—into the millions. Commas divide each group of three digits: the first comma from the right marks the thousands, the second marks the millions. In Chapter 4 of Saxon Math Intermediate 4, students read numbers like 3,750,000 as 'three million, seven hundred fifty thousand.' This skill prepares students to interpret population data, financial figures, and scientific measurements involving very large numbers.
Key Concepts
Property To write a whole number with seven to nine digits, use commas to separate groups of three digits, starting from the right. The first comma from the right marks the 'thousand' place, and the second comma marks the 'million' place, making large numbers easier to read.
Example 1. $25,000,000$ is read as 'twenty five million'. 2. $3,750,000$ is read as 'three million, seven hundred fifty thousand'. 3. $150,225,100$ is read as 'one hundred fifty million, two hundred twenty five thousand, one hundred'.
Explanation Think of commas as road signs for your numbers. The first one you pass yells 'THOUSAND!' and the second, even bigger one, shouts 'MILLION!' This system helps you read gigantic numbers without getting lost. It breaks them down into smaller, three digit chunks, making a number like one hundred million way less scary than it looks. It's like a GPS for numbers!
Common Questions
How do you read a seven-digit number?
Use commas to separate groups: the left group is millions, the middle is thousands, the right is ones. For 3,750,000: 'three million, seven hundred fifty thousand.'
What is the purpose of commas in large numbers?
Commas divide a number into three-digit groups from the right, making it clear which digits belong to millions, thousands, and ones. Without commas, large numbers are hard to read.
How do you write 150,225,100 in words?
One hundred fifty million, two hundred twenty-five thousand, one hundred.
When do Grade 4 students learn place values into the millions?
Seven-to-nine digit place values are covered in Chapter 4 of Saxon Math Intermediate 4, extending the six-digit place value introduced earlier.
How many digits are in one million?
One million (1,000,000) has seven digits. One billion (1,000,000,000) has ten digits.
How do commas help when comparing large numbers?
Commas let you see immediately which group of digits is largest. A seven-digit number is always greater than any six-digit number because its leading group is in the millions.