Fractions
In one line
A fraction shows a part of a whole: the bottom number says how many equal parts, and the top number says how many you have.
Parts of a fraction
Types of fractions
| Type | Meaning | Example |
|---|---|---|
| Proper | Numerator smaller than denominator (less than 1) | 2/5, 3/4 |
| Improper | Numerator equal to or bigger than denominator | 7/4, 5/5 |
| Mixed | A whole number and a proper fraction | 1¾ (same as 7/4) |
| Like | Same denominator | 1/8, 3/8, 5/8 |
| Unlike | Different denominators | 1/2, 2/3 |
Mixed → improper: 2⅓ = (2 × 3 + 1)/3 = 7/3. Improper → mixed: 11/4 = 11 ÷ 4 = 2 remainder 3 = 2¾.
Equivalent fractions and simplest form
- Multiply or divide the top and bottom by the same number to get an equivalent fraction: 1/2 = 2/4 = 3/6 = 50/100.
- A fraction is in its simplest form when the top and bottom have no common factor except 1.
- To simplify, divide both by their HCF: 18/24 → HCF is 6 → 3/4.
Advertisement
Comparing fractions
- Same denominator: bigger numerator, bigger fraction. 5/9 > 2/9.
- Same numerator: smaller denominator, bigger fraction. 1/3 > 1/5 (a pizza cut into 3 gives bigger slices than one cut into 5).
- Both different: change them to the same denominator using the LCM. 2/3 vs 3/4 → 8/12 vs 9/12 → 3/4 is bigger.
Adding and subtracting
Like fractionsAdd the tops, keep the bottom. 2/7 + 3/7 = 5/7.
Unlike fractions1/2 + 1/3: LCM of 2 and 3 is 6. 3/6 + 2/6 = 5/6.
3/4 − 1/6: LCM is 12. 9/12 − 2/12 = 7/12.
3/4 − 1/6: LCM is 12. 9/12 − 2/12 = 7/12.
Common mistakes
- Adding the bottoms too. 1/2 + 1/3 is not 2/5. Make the denominators the same first.
- Thinking a bigger denominator means a bigger fraction. 1/8 is smaller than 1/4.
- Forgetting to simplify. Always give the answer in its simplest form.
Quick check
Revise in 30 seconds
| Numerator / denominator | Parts taken / total equal parts |
|---|---|
| Proper | Top < bottom · Improper: top ≥ bottom · Mixed: whole + fraction |
| Equivalent | × or ÷ top and bottom by the same number |
| Simplest form | Divide both by the HCF |
| Add / subtract | Make denominators the same (LCM), then add or subtract tops |