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:
7,784 = 2 × 2 × 2 × 7 × 139 = 23 × 7 × 139
7,784 is a composite number.
Written with exponents:
39,996 = 2 × 2 × 3 × 3 × 11 × 101 = 22 × 32 × 11 × 101
39,996 is a composite number.
7,784/39,996 =
(7,784 ÷ 4) / (39,996 ÷ 4) =
1,946/9,999
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.
7,784/39,996 =
(23 × 7 × 139)/(22 × 32 × 11 × 101) =
((23 × 7 × 139) ÷ 22) / ((22 × 32 × 11 × 101) ÷ 22) =
(2 × 7 × 139)/(32 × 11 × 101) =
1,946/9,999
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
1,946/9,999 =
1,946 ÷ 9,999 =
0.194619461946 ≈
0.19