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:
1,572 = 2 × 2 × 3 × 131 = 22 × 3 × 131
1,572 is a composite number.
Written with exponents:
200,000 = 2 × 2 × 2 × 2 × 2 × 2 × 5 × 5 × 5 × 5 × 5 = 26 × 55
200,000 is a composite number.
1,572/200,000 =
(1,572 ÷ 4) / (200,000 ÷ 4) =
393/50,000
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.
1,572/200,000 =
(22 × 3 × 131)/(26 × 55) =
((22 × 3 × 131) ÷ 22) / ((26 × 55) ÷ 22) =
(3 × 131)/(24 × 55) =
393/50,000
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
393/50,000 =
393 ÷ 50,000 =
0.00786 ≈
0.01