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:
4,581 = 3 × 3 × 509 = 32 × 509
4,581 is a composite number.
Written with exponents:
123,720 = 2 × 2 × 2 × 3 × 5 × 1,031 = 23 × 3 × 5 × 1,031
123,720 is a composite number.
4,581/123,720 =
(4,581 ÷ 3) / (123,720 ÷ 3) =
1,527/41,240
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.
4,581/123,720 =
(32 × 509)/(23 × 3 × 5 × 1,031) =
((32 × 509) ÷ 3) / ((23 × 3 × 5 × 1,031) ÷ 3) =
(3 × 509)/(23 × 5 × 1,031) =
1,527/41,240
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
1,527/41,240 =
1,527 ÷ 41,240 =
0.037027158099 ≈
0.04