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:
78,138 = 2 × 3 × 3 × 3 × 1,447 = 2 × 33 × 1,447
78,138 is a composite number.
500,006 = 2 × 13 × 19,231
500,006 is a composite number.
78,138/500,006 =
(78,138 ÷ 2) / (500,006 ÷ 2) =
39,069/250,003
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.
78,138/500,006 =
(2 × 33 × 1,447)/(2 × 13 × 19,231) =
((2 × 33 × 1,447) ÷ 2) / ((2 × 13 × 19,231) ÷ 2) =
(33 × 1,447)/(13 × 19,231) =
39,069/250,003
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
39,069/250,003 =
39,069 ÷ 250,003 =
0.156274124711 ≈
0.16