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:
40 = 2 × 2 × 2 × 5 = 23 × 5
40 is a composite number.
500,000,046 = 2 × 3 × 7 × 13 × 409 × 2,239
500,000,046 is a composite number.
40/500,000,046 =
(40 ÷ 2) / (500,000,046 ÷ 2) =
20/250,000,023
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.
40/500,000,046 =
(23 × 5)/(2 × 3 × 7 × 13 × 409 × 2,239) =
((23 × 5) ÷ 2) / ((2 × 3 × 7 × 13 × 409 × 2,239) ÷ 2) =
(22 × 5)/(3 × 7 × 13 × 409 × 2,239) =
20/250,000,023
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
20/250,000,023 =
20 ÷ 250,000,023 =
0.00000008 ≈
0