2. Write the number as an improper fraction.
- 5.428 can be written as an improper fraction.
- An improper fraction = the numerator is larger than or equal to the denominator..
Write down the number divided by 1, as a fraction:
5.428 = 5.428/1
Turn the top number into a whole number.
- Multiply both the top and the bottom by the same number.
- This number is: 1,000.
- 1 followed by as many 0-s as the number of digits after the decimal point.
5.428/1 =
(5.428 × 1,000)/(1 × 1,000) =
5,428/1,000
3. Reduce (simplify) the fraction above:
5,428/1,000
to the lowest terms, to its simplest equivalent form, irreducible.
To reduce a fraction to the lowest terms divide the numerator and denominator by their greatest (highest) common factor (divisor), GCF.
Factor the numerator and denominator (prime factorization).
5,428 = 22 × 23 × 59
1,000 = 23 × 53
Calculate the greatest (highest) common factor (divisor), GCF.
Multiply all the common prime factors by the lowest exponents.
GCF (22 × 23 × 59; 23 × 53) = 22
Divide both the numerator and the denominator by their GCF.
5,428/1,000 =
(22 × 23 × 59)/(23 × 53) =
((22 × 23 × 59) ÷ 22) / ((23 × 53) ÷ 22) =
(23 × 59)/(2 × 53) =
1,357/250
4. The fraction is an improper one, rewrite it as a mixed number (mixed fraction):
- A mixed number = an integer number and a proper fraction, of the same sign.
- Example 1: 2 1/5; Example 2: - 1 3/7.
- A proper fraction = the numerator is smaller than the denominator.
1,357 ÷ 250 = 5, remainder = 107 ⇒
1,357 = 5 × 250 + 107 ⇒
1,357/250 =
(5 × 250 + 107) / 250 =
(5 × 250) / 250 + 107/250 =
5 + 107/250 =
5 107/250