Fundamentals · Lesson 1 of 9

Fractions & decimals

A fraction just means "this many of these equal parts." Once you can see it, turning it into a decimal is easy.

Explore

Drag the two sliders. The top number (numerator) is how many parts you shade; the bottom (denominator) is how many equal parts the whole is cut into.

Fraction 3/4 Decimal 0.75

Predict

Quick guess: set the bar to 1/2. Is 1/2 bigger or smaller than the 3/4 you started with?

How it works

To turn any fraction into a decimal, divide the top by the bottom. So 3 ÷ 4 = 0.75. The bar and pie show the same three-quarters; the decimal is just another way to write it.

Worked example

A pizza is cut into 8 slices and you eat 3. You ate 3/8. As a decimal that's 3 ÷ 8 = 0.375 — a bit more than a third of the pizza.

Common mistake

A bigger bottom number does not mean a bigger fraction. 1/8 is smaller than 1/2, because cutting the whole into more pieces makes each piece smaller.

Guided practice

Let's convert 2/5 together. Reveal each step when you're ready.

Your turn

Answer these to finish the lesson. Use a hint if you're stuck — that's allowed!

Recap