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:
123,740 = 2 × 2 × 5 × 23 × 269 = 22 × 5 × 23 × 269
123,740 is a composite number.
Written with exponents:
1,076 = 2 × 2 × 269 = 22 × 269
1,076 is a composite number.
123,740/1,076 =
(123,740 ÷ 1,076) / (1,076 ÷ 1,076) =
115/1 =
115
* 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.
123,740/1,076 =
(22 × 5 × 23 × 269)/(22 × 269) =
((22 × 5 × 23 × 269) ÷ (22 × 269)) / ((22 × 269) ÷ (22 × 269)) =
(5 × 23)/1 =
(5 × 23) =
115
* When it's 1, the denominator of the fraction can be omitted.