2. Write the number as an improper fraction.
- 315.76 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:
315.76 = 315.76/1
Turn the top number into a whole number.
- Multiply both the top and the bottom by the same number.
- This number is: 100.
- 1 followed by as many 0-s as the number of digits after the decimal point.
315.76/1 =
(315.76 × 100)/(1 × 100) =
31,576/100
3. Reduce (simplify) the fraction above:
31,576/100
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).
31,576 = 23 × 3,947
100 = 22 × 52
Calculate the greatest (highest) common factor (divisor), GCF.
Multiply all the common prime factors by the lowest exponents.
GCF (23 × 3,947; 22 × 52) = 22
Divide both the numerator and the denominator by their GCF.
31,576/100 =
(23 × 3,947)/(22 × 52) =
((23 × 3,947) ÷ 22) / ((22 × 52) ÷ 22) =
(2 × 3,947)/52 =
7,894/25
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.
7,894 ÷ 25 = 315, remainder = 19 ⇒
7,894 = 315 × 25 + 19 ⇒
7,894/25 =
(315 × 25 + 19) / 25 =
(315 × 25) / 25 + 19/25 =
315 + 19/25 =
315 19/25