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:
4,086 = 2 × 3 × 3 × 227 = 2 × 32 × 227
4,086 is a composite number.
Written with exponents:
13,840 = 2 × 2 × 2 × 2 × 5 × 173 = 24 × 5 × 173
13,840 is a composite number.
4,086/13,840 =
(4,086 ÷ 2) / (13,840 ÷ 2) =
2,043/6,920
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.
4,086/13,840 =
(2 × 32 × 227)/(24 × 5 × 173) =
((2 × 32 × 227) ÷ 2) / ((24 × 5 × 173) ÷ 2) =
(32 × 227)/(23 × 5 × 173) =
2,043/6,920
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
2,043/6,920 =
2,043 ÷ 6,920 =
0.295231213873 ≈
0.3