Place Value Symmetry
Visual diagram showing x10 and /10 relationships across the decimal point.
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Each place value is 10 times smaller than the one immediately to its left, and 10 times bigger than the one to its right.
Introduce the decimal point as a natural extension of the Indian place value system.
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Defining decimal notation as extending place value to the right.
The Indian place value system is based on the number 10. For a whole number like 281, each place value is 10 times bigger than the one immediately to its right. Equivalently, moving to the right means each place value is 10 times smaller (divided by 10).
Rules for pronouncing decimal numbers.
We read the whole number part normally, say "point", and then read the fractional digits individually.
Visual diagram showing x10 and /10 relationships across the decimal point.
Each place value is 10 times smaller than the one immediately to its left, and 10 times bigger than the one to its right.
Example of writing tenths and hundredths as decimals.
Problem. Write 234 tenths in decimal form.
Practice filling out decimal place values.
Let's write a quantity using decimal notation. We are given 2 ones, 3 tenths, and 5 hundredths.
This quantity can be expanded as 2 + \frac{}{10} + \frac{}{100}.
Combining these parts gives us the final decimal form of .
When reading this number aloud, we say "Two point five". Remember, we read digits after the decimal point individually.
Match numeric decimal to its verbal reading.
Terms
Definitions
Convert a given place value string into decimal form.
Follow the place value principles to convert and combine the expanded parts.
List the separate place value amounts you need to combine.
State what each place value name means mathematically.
Convert each individual amount into its standard numerical value.
Show the addition of all your converted values.
Write the final combined decimal number.
Does this answer make sense based on carrying over 10 of any unit?