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:
90 = 2 × 3 × 3 × 5 = 2 × 32 × 5
90 is a composite number.
Written with exponents:
55,568 = 2 × 2 × 2 × 2 × 23 × 151 = 24 × 23 × 151
55,568 is a composite number.
90/55,568 =
(90 ÷ 2) / (55,568 ÷ 2) =
45/27,784
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.
90/55,568 =
(2 × 32 × 5)/(24 × 23 × 151) =
((2 × 32 × 5) ÷ 2) / ((24 × 23 × 151) ÷ 2) =
(32 × 5)/(23 × 23 × 151) =
45/27,784
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
45/27,784 =
45 ÷ 27,784 =
0.001619637201 ≈
0