What Are Decimals?
Decimals are numbers that include a point (or dot) and digits after it. For example, 3.5, 0.25, and 12.75 are all decimals. The digits after the point represent parts of a whole number. This is why decimals are really useful in real life — especially when dealing with money, measurements, and science.
Think of it like a pizza cut into slices. A whole pizza is 1.0, half a pizza is 0.5, and a quarter is 0.25.
Multiplying Decimals
When you multiply decimals, the trick is to ignore the decimal points at first. Pretend they aren't there and multiply the numbers as if they were whole numbers. Once you've got your answer, count how many digits came after the decimal points in your original numbers, then put the decimal point back in the right place.
For example: 2.5 × 3.2. Ignore the decimals and multiply: 25 × 32 = 800. Now count: 2.5 has one digit after the point, and 3.2 has one digit after the point. That's two digits total. So count back two places from the right: 8.00, which is the same as 8.
Think of it like moving decimal points around. Each time you multiply by 10, the decimal point slides one place to the right, making the number bigger.
Dividing Decimals
Dividing decimals works differently. The easiest method is to turn the problem into one with whole numbers. If you're dividing by a decimal, multiply both numbers by 10, 100, or 1000 — whatever it takes to remove the decimal from the number you're dividing by.
For example: 7.5 ÷ 2.5. Multiply both by 10: 75 ÷ 25 = 3. That's your answer! The decimal point moves the same number of places in both numbers, so it doesn't change the final result.
Think of it like scaling up a recipe. If you multiply both ingredients by the same amount, the flavour stays the same — just in bigger quantities.
Real-World Uses
You'll use these skills whenever you buy things in shops, work out fuel costs, or measure ingredients for cooking. Understanding decimals helps you make sense of the world around you.