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:
84 = 2 × 2 × 3 × 7 = 22 × 3 × 7
84 is a composite number.
Written with exponents:
40,000,000,124 = 2 × 2 × 7 × 1,428,571,433 = 22 × 7 × 1,428,571,433
40,000,000,124 is a composite number.
84/40,000,000,124 =
(84 ÷ 28) / (40,000,000,124 ÷ 28) =
3/1,428,571,433
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.
84/40,000,000,124 =
(22 × 3 × 7)/(22 × 7 × 1,428,571,433) =
((22 × 3 × 7) ÷ (22 × 7)) / ((22 × 7 × 1,428,571,433) ÷ (22 × 7)) =
3/1,428,571,433 =
3/1,428,571,433
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
3/1,428,571,433 =
3 ÷ 1,428,571,433 =
0.0000000021 ≈
0