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:
2,690 = 2 × 5 × 269
2,690 is a composite number.
Written with exponents:
20,020 = 2 × 2 × 5 × 7 × 11 × 13 = 22 × 5 × 7 × 11 × 13
20,020 is a composite number.
2,690/20,020 =
(2,690 ÷ 10) / (20,020 ÷ 10) =
269/2,002
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.
2,690/20,020 =
(2 × 5 × 269)/(22 × 5 × 7 × 11 × 13) =
((2 × 5 × 269) ÷ (2 × 5)) / ((22 × 5 × 7 × 11 × 13) ÷ (2 × 5)) =
269/(2 × 7 × 11 × 13) =
269/2,002
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
269/2,002 =
269 ÷ 2,002 =
0.134365634366 ≈
0.13