What is a decimal?
A decimal is a number with a dot in it, like 0.5 or 2.3. The dot is called the decimal point. It splits the whole part from the small part.
Key idea
One half can be written as a decimal: ½ = 0.5. The number after the dot shows tenths.
Decimals in money
We use decimals with money every day. In RM2.50, the dot splits ringgit from sen: 2 ringgit and 50 sen. When you add decimals, keep the dots in a line so tenths add with tenths. A number line is a helpful way to see where a decimal like 0.5 sits between 0 and 1.
Worked example
Add 0.3 + 0.4. Keep the dots in a line.
0.3 + 0.4 = 0.7. (3 tenths + 4 tenths = 7 tenths.) We can check on a number line by counting on in tenths.
Remember
- The dot is the decimal point.
- ½ = 0.5.
- In money, the dot splits ringgit and sen.