- Definition
A decimal number is a number with a dot in it, like 3.75, where the numbers after the dot show parts of a whole, not full numbers.
In the number 5.2, the 5 is the whole number part and the .2 is the part that is less than one.
How to teach this in 30 seconds
Try this analogy: A decimal number is like money, where the dollars are the whole number and the cents are the parts of a dollar.
Ask your child: Look at this price tag. What part is whole dollars and what part is cents?
Common mix-up: Kids might think the number after the decimal point is a big whole number (like 75 in 3.75). The digits after the decimal point actually represent a value smaller than one whole.
Examples
- A price tag of $4.99 means 4 whole dollars and 99 parts of a dollar.
- A race time of 9.58 seconds means 9 whole seconds and 58 hundredths of another second.
- The number 1.5 is one whole and one half.
decimal number is a term used in Ontario’s Kindergarten to Grade 8 curriculum.
Where this shows up
+21 more mentions across the curriculum
The descriptions on this page are SmartStudy’s own original, plain-language writing — not the Ministry’s wording. They are aligned to the Ontario Curriculum, © King’s Printer for Ontario. For the Ministry’s official wording, see the source link below. SmartStudy is an independent service and is not affiliated with, endorsed by, or sponsored by the Government of Ontario or the Ministry of Education. Ontario Curriculum and Resources ↗
