1. Understanding Place Values
Place value is about knowing the value of all the digits in a number. You can use place values to read, write, compare and order numbers.
The value of a digit depends upon its place in a number. It is determined as ones, tens, hundreds, thousands,ten-thousands and so on, based on their position in the number. For example, consider the number 5968 - the place value of 6 is expressed as 6 tens, or 60. However, the place value of 6 in 9625 is expressed as 6 hundreds, or 600. Hence, despite being the same digit, its value depends on its position in the given numbers.
2. Whole number place value chart
The place value chart is a useful tool that helps us in finding the place value of each digit in a number. The place value of a digit increases by ten times as we move left on the place value chart.
The first row in the place value chart are the periods: Millions, Thousands and Ones.
2.1 How to Read and Write whole numbers
- Group the digits according to the period and place it in the place value chart.
- Use commas, between the period while writing the number.
- To spell out the number, start reading the digits from left to right in the place value chart.
Example: Consider a seven-digit number 2389476. Placing the number in the place value chart:
Using the commas between the periods to write the number: 2,389,476.
Spelling out the number, the digit in the millions period has to be read first, followed by the digit in the thousands period and the ones period.
So the number would be Two million, three hundred eighty-nine thousand, hundred and ten.
3. Decimal place value chart
It has both whole number and fractional part as shown below. From the decimal point in the chart, the place value of digit increases by ten times as we move right in the place value chart.
3.1 How to Read and Write decimals
In order to read a decimal:
- Read from left to right, as if it were a whole number followed by the place value of the rightmost digit.
- The decimal point is read as ‘and’.
Example: Consider the number 48.15.
The number can be read as Forty-eight and fifteen hundredths.
In order to write a decimal:
- The number before the ‘and’ is the whole number part, written to the left of the decimal point.
- The number after the ‘and’ is the fractional part, written to the right of the decimal point.
Example: Consider the number “Two fifty and twelve hundredths”.
Whole number part = Twenty-four
Fractional part = Twelve hundredths
Placing the digits in the place value chart:
Hence the number “Two fifty and twelve hundredths” can be written as 250.12.
