2. Write the mixed repeating (recurring) decimal number as an improper fraction.
1.0666667 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 = 1.0666667
Set up the second equation.
- Number of decimal places repeating: 2
Multiply both sides of the first equation by 102 = 100
y = 1.0666667
100 × y = 100 × 1.0666667
100 × y = 106.66667
Get the same number of decimal places as for y:
100 × y = 106.6666767
Note: 106.6666767 = 106.66667
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.
100 × y - y = 106.6666767 - 1.0666667 ⇒
(100 - 1) × y = 106.6666767 - 1.0666667 ⇒
We now have a new equation:
99 × y = 105.60001
Solve for y in the new equation.
99 × y = 105.60001 ⇒
y = 105.60001/99
Let the result written as a fraction.
Now we can write the number as a fraction.
According to our first equation:
y = 1.0666667
According to our calculations:
y = 105.60001/99
⇒ 1.0666667 = 105.60001/99
Get rid of the decimal places in the fraction above.
- Multiply the top and the bottom number by 100,000.
- 1 followed by as many 0-s as the number of digits after the decimal point.
1.0666667 = (105.60001 × 100,000)/(99 × 100,000)
1.0666667 = 10,560,001/9,900,000
3. Reduce (simplify) the fraction above:
10,560,001/9,900,000
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).
10,560,001 = 41 × 257,561
9,900,000 = 25 × 32 × 55 × 11
Calculate the greatest (highest) common factor (divisor), GCF.
Multiply all the common prime factors by the lowest exponents.
But, the numerator and the denominator have no common factors.
GCF (41 × 257,561; 25 × 32 × 55 × 11) = 1
The numerator and the denominator are coprime numbers (no common prime factors, GCF = 1). So, the fraction cannot be reduced (simplified): irreducible fraction.
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.
10,560,001 ÷ 9,900,000 = 1, remainder = 660,001 ⇒
10,560,001 = 1 × 9,900,000 + 660,001 ⇒
10,560,001/9,900,000 =
(1 × 9,900,000 + 660,001) / 9,900,000 =
(1 × 9,900,000) / 9,900,000 + 660,001/9,900,000 =
1 + 660,001/9,900,000 =
1 660,001/9,900,000