Every time you move right in the number, the place value gets 10 times smaller.
Just like on the other side of the decimal point, the numbers get 10 times smaller every time you move right a place value. For instance, 0. 1 is ten times bigger than 0. 01, which in turn is ten times bigger than 0. 001, just like how 10 is ten times bigger than 1.
In the US, a dime is one-tenth of a dollar, or $0. 10. Coins can be a helpful way to think about decimals.
A penny is one hundredth of a dollar, or $0. 01.
When you’re just learning decimals, you might stick with just the tenths and hundredths place. The thousandths place will be useful later on, though.
If you’re confused about why you can ignore zeros at the end, think of the decimals as fractions. 0. 5 is 5/10, 0. 50 is 50/100 and 0. 500 is 500/1000. All of those are the same fraction, ½.
For example, 3,450. 02 would be three thousand four hundred fifty and two hundredths.
The word “and” helps people know that you are switching from whole numbers to parts of numbers.
You don’t need the word “and” to mark the transition between whole numbers and decimal numbers in numbers less than 1 because there is no transition.
Don’t write the word “and” other than to represent the decimal point. For instance, write . 103 as one hundred three thousandths, not one hundred and three thousandths.
Remember to ignore zeros at the end of decimals. Write 0. 890 as eighty-nine hundredths, not eight hundred ninety thousandths.
