2. Write the number as an improper fraction.
- 641.8984 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:
641.8984 = 641.8984/1
Turn the top number into a whole number.
- Multiply both the top and the bottom by the same number.
- This number is: 10,000.
- 1 followed by as many 0-s as the number of digits after the decimal point.
641.8984/1 =
(641.8984 × 10,000)/(1 × 10,000) =
6,418,984/10,000
3. Reduce (simplify) the fraction above:
6,418,984/10,000
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).
6,418,984 = 23 × 11 × 13 × 31 × 181
10,000 = 24 × 54
Calculate the greatest (highest) common factor (divisor), GCF.
Multiply all the common prime factors by the lowest exponents.
GCF (23 × 11 × 13 × 31 × 181; 24 × 54) = 23
Divide both the numerator and the denominator by their GCF.
6,418,984/10,000 =
(23 × 11 × 13 × 31 × 181)/(24 × 54) =
((23 × 11 × 13 × 31 × 181) ÷ 23) / ((24 × 54) ÷ 23) =
(11 × 13 × 31 × 181)/(2 × 54) =
802,373/1,250
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.
802,373 ÷ 1,250 = 641, remainder = 1,123 ⇒
802,373 = 641 × 1,250 + 1,123 ⇒
802,373/1,250 =
(641 × 1,250 + 1,123) / 1,250 =
(641 × 1,250) / 1,250 + 1,123/1,250 =
641 + 1,123/1,250 =
641 1,123/1,250