2. Write the number as an improper fraction.
- 2.8078 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:
2.8078 = 2.8078/1
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.
2.8078/1 =
(2.8078 × 10,000)/(1 × 10,000) =
28,078/10,000
3. Reduce (simplify) the fraction above:
28,078/10,000
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).
28,078 = 2 × 101 × 139
10,000 = 24 × 54
Calculate the greatest (highest) common factor (divisor), GCF.
Multiply all the common prime factors by the lowest exponents.
GCF (2 × 101 × 139; 24 × 54) = 2
Divide both the numerator and the denominator by their GCF.
28,078/10,000 =
(2 × 101 × 139)/(24 × 54) =
((2 × 101 × 139) ÷ 2) / ((24 × 54) ÷ 2) =
(101 × 139)/(23 × 54) =
14,039/5,000
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.
14,039 ÷ 5,000 = 2, remainder = 4,039 ⇒
14,039 = 2 × 5,000 + 4,039 ⇒
14,039/5,000 =
(2 × 5,000 + 4,039) / 5,000 =
(2 × 5,000) / 5,000 + 4,039/5,000 =
2 + 4,039/5,000 =
2 4,039/5,000