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:
19,638 = 2 × 3 × 3 × 1,091 = 2 × 32 × 1,091
19,638 is a composite number.
67,474 = 2 × 11 × 3,067
67,474 is a composite number.
19,638/67,474 =
(19,638 ÷ 2) / (67,474 ÷ 2) =
9,819/33,737
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.
19,638/67,474 =
(2 × 32 × 1,091)/(2 × 11 × 3,067) =
((2 × 32 × 1,091) ÷ 2) / ((2 × 11 × 3,067) ÷ 2) =
(32 × 1,091)/(11 × 3,067) =
9,819/33,737
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
9,819/33,737 =
9,819 ÷ 33,737 =
0.291045439725 ≈
0.29