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:
42 = 2 × 3 × 7
42 is a composite number.
Written with exponents:
500,000,036 = 2 × 2 × 23 × 1,021 × 5,323 = 22 × 23 × 1,021 × 5,323
500,000,036 is a composite number.
42/500,000,036 =
(42 ÷ 2) / (500,000,036 ÷ 2) =
21/250,000,018
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.
42/500,000,036 =
(2 × 3 × 7)/(22 × 23 × 1,021 × 5,323) =
((2 × 3 × 7) ÷ 2) / ((22 × 23 × 1,021 × 5,323) ÷ 2) =
(3 × 7)/(2 × 23 × 1,021 × 5,323) =
21/250,000,018
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
21/250,000,018 =
21 ÷ 250,000,018 =
0.000000084 ≈
0