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Rational Numbers Operation
Concept:
A rational number can be represented in the form of a/b, where a and b are integers, and b is not zero.
For example, a/b is called a fraction, where a is the numerator of the fraction and b is the denominator of the fraction.
Concept:
Two fraction are said to be equivalent if they have the same value but different forms.
Example:
For example, 2/3, 4/6, -6/-9.
We denote two equivalent fractions by writing an equal sign between them, 2/3 = 4/6 = -6/-9
Concept:
Two fractions are equivalent, if their cross products are equal.
Concept:
Addition and subtraction of fractions
Concept:
The least common denominator, or LCD
Example 1:
Solution:
The denominators are factored as : 15 = 3 × 5 and 6 = 2 × 3
The prime factors are 3, 5, 2, and therefore the LCD of the fractions is 3 × 5 × 2 = 30
Example 2:
Solution:
Writing the denominators in factored form, 18 = 3 × 3 × 2 = 32 × 2 and 27 = 3 × 3 × 3 = 33
so that, the LCD of the fractions is 33 × 2 = 54
Concept:
Multiplication and Division of Fractions