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:
4,986 = 2 × 3 × 3 × 277 = 2 × 32 × 277
4,986 is a composite number.
99,999,970 = 2 × 5 × 7 × 1,428,571
99,999,970 is a composite number.
4,986/99,999,970 =
(4,986 ÷ 2) / (99,999,970 ÷ 2) =
2,493/49,999,985
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.
4,986/99,999,970 =
(2 × 32 × 277)/(2 × 5 × 7 × 1,428,571) =
((2 × 32 × 277) ÷ 2) / ((2 × 5 × 7 × 1,428,571) ÷ 2) =
(32 × 277)/(5 × 7 × 1,428,571) =
2,493/49,999,985
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
2,493/49,999,985 =
2,493 ÷ 49,999,985 =
0.000049860015 ≈
0