2. Write the mixed repeating (recurring) decimal number as an improper fraction.
4.23232327 can be written as an improper fraction.
- The numerator is larger than or equal to the denominator.
Set up the first equation.
- Let y equal the decimal number:
y = 4.23232327
Set up the second equation.
- Number of decimal places repeating: 1
Multiply both sides of the first equation by 101 = 10
y = 4.23232327
10 × y = 10 × 4.23232327
10 × y = 42.3232327
Get the same number of decimal places as for y:
10 × y = 42.32323277
Note: 42.32323277 = 42.3232327
Subtract the first equation from the second one.
- Having the same number of decimal places ...
- The repeating pattern drops off by subtracting the two equations.
10 × y - y = 42.32323277 - 4.23232327 ⇒
(10 - 1) × y = 42.32323277 - 4.23232327 ⇒
We now have a new equation:
9 × y = 38.0909095
Solve for y in the new equation.
9 × y = 38.0909095 ⇒
y = 38.0909095/9
Let the result written as a fraction.
Now we can write the number as a fraction.
According to our first equation:
y = 4.23232327
According to our calculations:
y = 38.0909095/9
⇒ 4.23232327 = 38.0909095/9
Get rid of the decimal places in the fraction above.
- Multiply the top and the bottom number by 10,000,000.
- 1 followed by as many 0-s as the number of digits after the decimal point.
4.23232327 = (38.0909095 × 10,000,000)/(9 × 10,000,000)
4.23232327 = 380,909,095/90,000,000
3. Reduce (simplify) the fraction above:
380,909,095/90,000,000
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).
380,909,095 = 5 × 72 × 232 × 2,939
90,000,000 = 27 × 32 × 57
Calculate the greatest (highest) common factor (divisor), GCF.
Multiply all the common prime factors by the lowest exponents.
GCF (5 × 72 × 232 × 2,939; 27 × 32 × 57) = 5
Divide both the numerator and the denominator by their GCF.
380,909,095/90,000,000 =
(5 × 72 × 232 × 2,939)/(27 × 32 × 57) =
((5 × 72 × 232 × 2,939) ÷ 5) / ((27 × 32 × 57) ÷ 5) =
(72 × 232 × 2,939)/(27 × 32 × 56) =
76,181,819/18,000,000
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.
76,181,819 ÷ 18,000,000 = 4, remainder = 4,181,819 ⇒
76,181,819 = 4 × 18,000,000 + 4,181,819 ⇒
76,181,819/18,000,000 =
(4 × 18,000,000 + 4,181,819) / 18,000,000 =
(4 × 18,000,000) / 18,000,000 + 4,181,819/18,000,000 =
4 + 4,181,819/18,000,000 =
4 4,181,819/18,000,000