Decimals are numbers that show parts of a whole, and they’re separated by a decimal point.
Here are some key points about decimals:
Reason for using decimals:
When we cut things into smaller parts (like pieces of cake).
When we count money (like 10.50).
When we measure things (like height: 4.8 feet tall).
When we work with fractions (like ½ = 0.5).
Example:
If you eat half of a pizza, that is 0.5 pizza.
If you drink a quarter liter of water, that is 0.25 liter.
Parts of a decimal number:
Whole Number Part (before the dot) – 12
Decimal Part (after the dot) – 34
The decimal point separates the whole number from the decimal part.
So, 12.34 means 12 wholes and 34 parts out of 100.
Place values in decimals:
Just like in whole numbers, decimal numbers also have place values.
6.782 = 6 + 7/10 + 8/100 + 2/1000.
Understanding decimal places:
1st place after the decimal – TENTHS (Example: 0.1)
2nd place after the decimal – HUNDREDTHS (Example: 0.01)
3rd place after the decimal – THOUSANDTHS (Example: 0.001)
Decimals and fractions:
Decimals are another way to write fractions!
Example: 1/2 = 0.5 |Â Example: 3/4 = 0.75
Operating with decimals:
Addition, subtraction, multiplication, and division of decimals are similar to their whole number counterparts.
Conversion between fractions and decimals:
Decimal to fraction: 0.25 = 25/100 = 1/4
Fraction to decimal: 1/2 = 0.5
