2. Write the pure repeating (recurring) decimal number as an improper fraction.
1.5 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 = 1.5
Set up the second equation.
- Number of decimal places repeating: 1
Multiply both sides of the first equation by 101 = 10
y = 1.5
10 × y = 10 × 1.5
10 × y = 15.5
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 = 15.5 - 1.5 ⇒
(10 - 1) × y = 15.5 - 1.5 ⇒
We now have a new equation:
9 × y = 14
Solve for y in the new equation.
9 × y = 14 ⇒
y = 14/9
Let the result written as a fraction.
Now we can write the number as a fraction.
According to our first equation:
y = 1.5
According to our calculations:
y = 14/9
⇒ 1.5 = 14/9
3. Reduce (simplify) the fraction above:
14/9
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).
14 = 2 × 7
9 = 32
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 (2 × 7; 32) = 1
The numerator and the denominator are coprime numbers (no common prime factors, GCF = 1). So, the fraction cannot be reduced (simplified): irreducible fraction.