ABE Math Tutorials/Whole numbers/Place value
Place value
Whole numbers |
Introduction | Place value | Rounding | Long addition & subtraction | Long Multiplication | Long division | Expressing operations | Word problems | Order of operations | "Set-up" problems | Cost and distance problems | Introduction to algebra | Powers of 10 | Estimation | Not enough info | Homework
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Have you ever thought about what the number "14" means?
First we write down a digit "1", then we write down a digit "4". What does this mean? Does it mean "1 + 4" ? Does it mean "1 x 4" ? Of course not! We realize that the digit "1" doesn't really mean "1" at all; it really stands for "10". The number "14" means one group of 10 plus four ones. |
Words to Know
Now let's consider a bigger number, like 4,971. When we say this number out loud, we can hear what the digits stand for: 4 thousand, nine hundred and seventy-one. This means: 4 thousands plus 9 hundreds plus 7 tens (the word "seventy" actually means "seven-tens") plus one. Mathematically, we say:
This idea, that every digit in a number has its place, is called place value.Now, let's look at an even larger number: 6,408,554 (6 million, four-hundred-and-eight thousand, five hundred and fifty-four). To figure out what the place value is of each digit in this number, we can write it down in a table like the one below. |
millions | hundred thousands | ten thousands | thousands | hundreds | tens | ones |
6 | 4 | 0 | 8 | 5 | 5 | 4 |
Number 6,408,554
Notice that the last digit in a number always goes in the ones' place; the second-to-last digit always goes in the tens' place; the third-to-last digit (if there is one) always goes in the hundreds' place; and so on. Look at this number (6,408,554) once again.}}
What is the place value of the 8?: When you look at the table, you can see that the 8 is in the thousands place. What is the place value of the 6?: You can see that the 6 is in the millions place. What is the place value of the 0?:The 0 (zero) is in the ten-thousands place. This means that there are no ten-thousands in this number, but if we left out the zero, we would get an entirely different number (648,554)!
In the table below, the first three numbers on the right-hand side have been separated into their place values. Try writing out the other three numbers into the table (you can print this page off to do this; or just write out the numbers on a piece of scrap paper):
millions | hundred thousands | ten thousands | thousands | hundreds | tens | ones |
---|---|---|---|---|---|---|
3 | 4 | 6 | 9 | 1 | 1 | 4 |
4 | 2 | 9 | ||||
7 | 0 | 0 | 0 | 1 | ||
Now try answering the following questions:
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