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:
6,666,670 = 2 × 5 × 666,667
6,666,670 is a composite number.
Written with exponents:
39,999,942 = 2 × 3 × 3 × 2,222,219 = 2 × 32 × 2,222,219
39,999,942 is a composite number.
6,666,670/39,999,942 =
(6,666,670 ÷ 2) / (39,999,942 ÷ 2) =
3,333,335/19,999,971
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.
6,666,670/39,999,942 =
(2 × 5 × 666,667)/(2 × 32 × 2,222,219) =
((2 × 5 × 666,667) ÷ 2) / ((2 × 32 × 2,222,219) ÷ 2) =
(5 × 666,667)/(32 × 2,222,219) =
3,333,335/19,999,971
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
3,333,335/19,999,971 =
3,333,335 ÷ 19,999,971 =
0.166666991667 ≈
0.17