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:
66,666,668 = 2 × 2 × 19 × 739 × 1,187 = 22 × 19 × 739 × 1,187
66,666,668 is a composite number.
Written with exponents:
399,999,996 = 2 × 2 × 3 × 3 × 11 × 73 × 101 × 137 = 22 × 32 × 11 × 73 × 101 × 137
399,999,996 is a composite number.
66,666,668/399,999,996 =
(66,666,668 ÷ 4) / (399,999,996 ÷ 4) =
16,666,667/99,999,999
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.
66,666,668/399,999,996 =
(22 × 19 × 739 × 1,187)/(22 × 32 × 11 × 73 × 101 × 137) =
((22 × 19 × 739 × 1,187) ÷ 22) / ((22 × 32 × 11 × 73 × 101 × 137) ÷ 22) =
(19 × 739 × 1,187)/(32 × 11 × 73 × 101 × 137) =
16,666,667/99,999,999
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
16,666,667/99,999,999 =
16,666,667 ÷ 99,999,999 =
0.166666671667 ≈
0.17