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:
188 = 2 × 2 × 47 = 22 × 47
188 is a composite number.
Written with exponents:
399,996 = 2 × 2 × 3 × 3 × 41 × 271 = 22 × 32 × 41 × 271
399,996 is a composite number.
188/399,996 =
(188 ÷ 4) / (399,996 ÷ 4) =
47/99,999
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.
188/399,996 =
(22 × 47)/(22 × 32 × 41 × 271) =
((22 × 47) ÷ 22) / ((22 × 32 × 41 × 271) ÷ 22) =
47/(32 × 41 × 271) =
47/99,999
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
47/99,999 =
47 ÷ 99,999 =
0.0004700047 ≈
0