What is 12.317142714271427142... as a Fraction?

12.317142 equals 12315911999900 as a fraction.

How do you turn 12.317142 repeating into a fraction?

Detailed Answer:

Step 1: To convert 12.317142 repeating into a fraction, begin writing this simple equation:

n = 12.317142 (equation 1)

Step 2: Notice that there are 4 digits in the repeating block (7142) and 2 digits in the non-repeating part (31). Multiply both sides by 10⁶ = 1000000.

1000000 × n = 12317142.7142 (equation 2)

Step 3: Now subtract equation 1 from equation 2 to cancel the repeating block (or repetend) out.

1000000 × n = 12317142.7142
    100 × n = 12.317142
 999900 × n = 12315911

n = 12315911999900 (answer)

12.317142 = 12315911999900 as the lowest possible fraction.

As the numerator is greater than the denominator, we have an improper fraction, so we can also express it as a mixed number, thus 12315911999900 is also equal to 12317111999900 when expressed as a mixed number.

The repeating decimal 12.317142 (vinculum notation) has a repeated block length of 4. It is also represented as 12.31714271427142... (ellipsis notation) which equals approximately 12.3171427142714271427142 (decimal approximation)(*).

The recurring decimal 12.317142 can be written as a ratio of two integers having 12315911 as the numerator and 999900 as the denominator. So, it is a rational number (named after ratio). It can be shown that a number is rational if its decimal representation is repeating or terminating.

(*) At present, there is no single universally accepted notation or phrasing for repeating decimals.