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:
21,832 = 2 × 2 × 2 × 2,729 = 23 × 2,729
21,832 is a composite number.
Written with exponents:
40,000 = 2 × 2 × 2 × 2 × 2 × 2 × 5 × 5 × 5 × 5 = 26 × 54
40,000 is a composite number.
21,832/40,000 =
(21,832 ÷ 8) / (40,000 ÷ 8) =
2,729/5,000
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.
21,832/40,000 =
(23 × 2,729)/(26 × 54) =
((23 × 2,729) ÷ 23) / ((26 × 54) ÷ 23) =
2,729/(23 × 54) =
2,729/5,000
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
2,729/5,000 =
2,729 ÷ 5,000 =
0.5458 ≈
0.55