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:
90 = 2 × 3 × 3 × 5 = 2 × 32 × 5
90 is a composite number.
40,000,000,146 = 2 × 3 × 1,049 × 6,355,259
40,000,000,146 is a composite number.
90/40,000,000,146 =
(90 ÷ 6) / (40,000,000,146 ÷ 6) =
15/6,666,666,691
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.
90/40,000,000,146 =
(2 × 32 × 5)/(2 × 3 × 1,049 × 6,355,259) =
((2 × 32 × 5) ÷ (2 × 3)) / ((2 × 3 × 1,049 × 6,355,259) ÷ (2 × 3)) =
(3 × 5)/(1,049 × 6,355,259) =
15/6,666,666,691
As a decimal number:
Simply divide the numerator by the denominator, without a remainder, as shown below:
15/6,666,666,691 =
15 ÷ 6,666,666,691 =
0.00000000225 ≈
0