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:
12,200 = 2 × 2 × 2 × 5 × 5 × 61 = 23 × 52 × 61
12,200 is a composite number.
Written with exponents:
699,880 = 2 × 2 × 2 × 5 × 17,497 = 23 × 5 × 17,497
699,880 is a composite number.
12,200/699,880 =
(12,200 ÷ 40) / (699,880 ÷ 40) =
305/17,497
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.
12,200/699,880 =
(23 × 52 × 61)/(23 × 5 × 17,497) =
((23 × 52 × 61) ÷ (23 × 5)) / ((23 × 5 × 17,497) ÷ (23 × 5)) =
(5 × 61)/17,497 =
305/17,497
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
305/17,497 =
305 ÷ 17,497 =
0.017431559696 ≈
0.02