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:
123,768 = 2 × 2 × 2 × 3 × 3 × 3 × 3 × 191 = 23 × 34 × 191
123,768 is a composite number.
Written with exponents:
54 = 2 × 3 × 3 × 3 = 2 × 33
54 is a composite number.
123,768/54 =
(123,768 ÷ 54) / (54 ÷ 54) =
2,292/1 =
2,292
* When it's 1, the denominator of the fraction can be omitted.
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.
123,768/54 =
(23 × 34 × 191)/(2 × 33) =
((23 × 34 × 191) ÷ (2 × 33)) / ((2 × 33) ÷ (2 × 33)) =
(22 × 3 × 191)/1 =
(22 × 3 × 191) =
2,292
* When it's 1, the denominator of the fraction can be omitted.
As a percentage:
- A percentage value p% is equal to the fraction: p/100, for any decimal number p. So, we need to change the form of the number calculated above, to show a denominator of 100.
- To do that, multiply the number by the fraction 100/100.
- The value of the fraction 100/100 = 1, so by multiplying the number by this fraction the result is not changing, only the form.
2,292 =
2,292 × 100/100 =
(2,292 × 100)/100 =
229,200/100 =
229,200%
- In other words:
- (1) Calculate the fraction's value, (2) multiply that number by 100, and (3) add the percent sign % to it.
The final answer:
written in three ways