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:
80 = 2 × 2 × 2 × 2 × 5 = 24 × 5
80 is a composite number.
500,000,098 = 2 × 13 × 157 × 122,489
500,000,098 is a composite number.
80/500,000,098 =
(80 ÷ 2) / (500,000,098 ÷ 2) =
40/250,000,049
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.
80/500,000,098 =
(24 × 5)/(2 × 13 × 157 × 122,489) =
((24 × 5) ÷ 2) / ((2 × 13 × 157 × 122,489) ÷ 2) =
(23 × 5)/(13 × 157 × 122,489) =
40/250,000,049
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
40/250,000,049 =
40 ÷ 250,000,049 =
0.00000016 ≈
0