Fractions and BODMAS
Fractions can be combined in expressions, but the order of operations must be respected.
Operations
Use a common denominator for addition and subtraction. Multiply numerators and denominators for multiplication. To divide, multiply by the reciprocal. Simplify the final fraction.
BODMAS
BODMAS means Brackets, Orders, Division and Multiplication, Addition and Subtraction. Division and multiplication are performed from left to right, as are addition and subtraction.
Worked examples
- 2/3 + 1/4 = 8/12 + 3/12 = 11/12.
- 3/5 ÷ 9/10 = 3/5 × 10/9 = 2/3.
- 1/2 + 3/4 × 2/3 = 1/2 + 1/2 = 1 because multiplication comes first.
Practice
- Evaluate 5/6 − 1/9.
- Calculate 7/8 × 4/21.
- Evaluate (2/3 + 1/6) ÷ 5/6.
