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:
1,512 = 2 × 2 × 2 × 3 × 3 × 3 × 7 = 23 × 33 × 7
1,512 is a composite number.
Written with exponents:
8,000 = 2 × 2 × 2 × 2 × 2 × 2 × 5 × 5 × 5 = 26 × 53
8,000 is a composite number.
1,512/8,000 =
(1,512 ÷ 8) / (8,000 ÷ 8) =
189/1,000
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.
1,512/8,000 =
(23 × 33 × 7)/(26 × 53) =
((23 × 33 × 7) ÷ 23) / ((26 × 53) ÷ 23) =
(33 × 7)/(23 × 53) =
189/1,000
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
189/1,000 =
189 ÷ 1,000 =
0.189 ≈
0.19