Common Fractions (Operations)
Add, subtract, multiply and divide common fractions
Operations with Common Fractions
In Grade 6 we add, subtract, multiply and divide fractions. To add or subtract, find a common denominator. To multiply, multiply across (numerator × numerator, denominator × denominator).
Example
Multiplying Fractions
2/3 × 4/5 = (2×4)/(3×5) = 8/15
1/2 × 3/4 = 3/8
3/5 × 5/6 = 15/30 = 1/2 (simplify by dividing by 15)
Example
Dividing Fractions
To divide fractions: flip the second fraction and multiply!
3/4 ÷ 1/2 = 3/4 × 2/1 = 6/4 = 3/2 = 1½
2/5 ÷ 3/4 = 2/5 × 4/3 = 8/15
Note
Remember
Multiply: straight across. Divide: flip and multiply. Add/subtract: find common denominator first. Always simplify your final answer.
Key Vocabulary
Common denominatorA shared denominator used to add or subtract fractions
ReciprocalA fraction flipped upside down (e.g. reciprocal of 2/3 is 3/2)
SimplifyReduce a fraction to lowest terms
Mixed numberA whole number and a fraction together (e.g. 1½)
Improper fractionA fraction where the numerator is larger than the denominator
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Common denominator
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