Converting and comparing fractions
Numerator and denominator, comparing, equivalent fractions and adding and subtracting fractions. Tenths, hundredths and the decimal comma; comparing and calculating with decimals. Read one part at a time and tap “I know this”. Then test yourself in the quiz.
Know it already? Jump straight to the quiz
What is a fraction?
A fraction is part of a whole. The denominator (bottom) says into how many equal parts the whole is cut; the numerator (top) says how many parts we have.
Compare, equivalent and simplify
- Same denominator: bigger numerator = bigger fraction: ⅗ > ⅖.
- Same numerator: bigger denominator = smaller pieces: ⅓ > ⅕.
- Equivalent fractions: multiply or divide top and bottom by the same number: ½ = ²⁄₄ = ³⁄₆.
- Simplify: divide top and bottom by the same factor: ⁶⁄₈ = ¾.
Adding and subtracting
First make the denominators the same, then add only the numerators: ½ + ¼ = ²⁄₄ + ¼ = ¾.
Never add the denominators: ½ + ¼ is not ²⁄₆.
Multiply: top × top, bottom × bottom: ⅔ × ¾ = ⁶⁄₁₂ = ½. Divide: flip the second fraction and multiply: ½ ÷ ¼ = ½ × ⁴⁄₁ = 2.
Subtracting mixed numbers: 2½ − 1⅔ = ⁵⁄₂ − ⁵⁄₃ = ¹⁵⁄₆ − ¹⁰⁄₆ = ⁵⁄₆. Fraction of an amount: ⅗ of 40 = 40 ÷ 5 × 3 = 24.
Grade 7: unlike denominators and multiplying
- Unlike denominators: find the LCM of the denominators. ⅔ + ¼ = ⁸⁄₁₂ + ³⁄₁₂ = ¹¹⁄₁₂.
- Mixed number to improper fraction: 2¾ = (2 × 4 + 3)⁄4 = ¹¹⁄₄.
- Multiply: numerator × numerator and denominator × denominator. ⅔ × ¾ = ⁶⁄₁₂ = ½.
- With mixed numbers: first make them improper fractions. 1½ × ⅔ = ³⁄₂ × ⅔ = ⁶⁄₆ = 1.
- Write the answer in its simplest form: divide numerator and denominator by their HCF.
Decimal fractions
The decimal comma separates the whole number from the parts. After the comma: tenths, hundredths, thousandths.
| Fraction | Decimal |
|---|---|
| ½ | 0,5 |
| ¼ | 0,25 |
| ¾ | 0,75 |
| ¹⁄₁₀ | 0,1 |
| ³⁄₁₀₀ | 0,03 |
0,5 is bigger than 0,45: compare tenths first (5 tenths vs 4 tenths). More digits after the comma do not make a number bigger.
Place value: in 4,37 the 3 is worth 3 tenths (0,3) and the 7 is worth 7 hundredths (0,07). From small to big: 0,09; 0,35; 0,4; 0,5. Counting in hundredths: 0,97; 0,98; 0,99; 1,00; 1,01.
Calculating with decimals
- Add and subtract: line up the commas: 3,5 + 1,25 = 4,75.
- × 10: the comma moves one place right: 3,45 × 10 = 34,5.
- ÷ 10: the comma moves one place left: 3,45 ÷ 10 = 0,345.
- × 100: the comma moves two places right: 3,45 × 100 = 345; ÷ 100: two places left: 45 ÷ 100 = 0,45.
- Multiply 0,3 × 0,2: 3 × 2 = 6; two digits after the comma → 0,06.
Three decimal places
- Thousandths: 3,147 = 3 + 0,1 + 0,04 + 0,007.
- Round to 2 decimal places: look at the third digit. 3,147 → 3,15; 6,082 → 6,08.
- Multiply: 2,345 × 3 = 7,035. 0,4 × 0,3 = 0,12: count the decimal places in the question (1 + 1 = 2): the answer has that many places.
- Divide by a whole number: 4,326 ÷ 3 = 1,442. Check with rounding or a calculator.
Remember this and test yourself
- Denominator = number of equal parts; numerator = how many we have.
- After the comma: tenths, hundredths, thousandths.
- Bigger denominator = smaller pieces.
- ½ = 0,5; ¼ = 0,25; ¾ = 0,75.
- Equivalent: multiply top and bottom by the same number.
- Compare tenths first, then hundredths.
Write these points in your book. Read them again the night before the test.

The denominator names the kind of piece; the numerator counts how many you have.
Important words
First say the answer yourself, then turn the card over.
Match column A to column B
Tap a word in column A, then its meaning in column B. You can also start in column B.
True or false?
Read the question and the answer. Is the answer right? Tap True or False.
Now the real quiz!
The quiz has many more questions on this topic. Every question shows straight away whether you are right and explains why.
Take the quiz: Converting and comparing fractions- Let your child work the examples on paper and explain them to you.
- The ticks (“I know this”) are saved on this device only. We never ask for names or emails.
Follows CAPS for Grade 7 Mathematics. Always check your teacher’s notes and textbook too.

