To reduce a fraction to the lowest terms equivalent: divide the numerator and denominator by their greatest common factor, GCF
To calculate the greatest common factor, GCF:
- 1. Factor the numerator and the denominator (into prime factors), build their prime factorizations.
- 2. Multiply all their common prime factors, taken by the lowest exponents.
1. Factor the numerator and the denominator:
To factor a number (into prime factors) - or, in other words, to break it down to prime factors - or, in other words, to build its prime factorization: find the prime numbers that multiply together to get that number.
The prime factorizations:
Written with exponents:
123,708 = 2 × 2 × 3 × 13 × 13 × 61 = 22 × 3 × 132 × 61
123,708 is a composite number.
Written with exponents:
676 = 2 × 2 × 13 × 13 = 22 × 132
676 is a composite number.
123,708/676 =
(123,708 ÷ 676) / (676 ÷ 676) =
183/1 =
183
* When it's 1, the denominator of the fraction can be omitted.
Yet another method to reduce the fraction
To reduce a fraction without calculating the GCF: factor its numerator and denominator, then all the common prime factors are easily identified and crossed out.
123,708/676 =
(22 × 3 × 132 × 61)/(22 × 132) =
((22 × 3 × 132 × 61) ÷ (22 × 132)) / ((22 × 132) ÷ (22 × 132)) =
(3 × 61)/1 =
(3 × 61) =
183
* When it's 1, the denominator of the fraction can be omitted.