# Place value and decimals

Contents
To really understand how decimal numbers work, we need a deep understanding of place value. The big picture goal of these tutorials is to connect decimal place value to the idea of multiplying by 10.

## Decimal place value intro

Learn the basics of decimal place value.

## Decimals in expanded form

Learn how to write a decimal like 3.14 in expanded form (3 + 0.1 + 0.04).

## Decimals in written form

Learn how to write decimals like 3.14 in words as "three and fourteen hundredths".

## Comparing decimals

Learn to tell which of two decimal numbers is bigger by thinking about place value.

## Rounding decimals

Learn how to round decimal numbers to specific place values. For example, round 3.14159 to the nearest hundredth as 3.14.

## Multiplying and dividing whole numbers by 10, 100, and 1000

Learn how to, for example, multiply 560 by 100 to get 56,000.

## Multiplying and dividing decimals by 10, 100, and 1000

Learn how to, for example, multiply 34.5 by 100 to get 3450.

## Powers of 10

Learn how exponents are a simpler way to write something like 10x10x10.

## Multiplying and dividing with powers of 10

Learn how to shift the decimal point when you multiply and divide by powers of ten.

## Comparing decimal place values

For a number like 34.135, learn how to compare the 3 in the tens place to the 3 in the hundredths place.

## Regrouping decimal numbers

Let's tackle some more challenging problems that stretch our understanding of decimal place value. These problems involve regrouping place values in interesting ways.