What is 18.21285285285... as a Fraction?

18.21285 equals 1516228325 as a fraction.

How do you turn 18.21285 repeating into a fraction?

Detailed Answer:

Step 1: To convert 18.21285 repeating into a fraction, begin writing this simple equation:

n = 18.21285 (equation 1)

Step 2: Notice that there are 3 digits in the repeating block (285) and 2 digits in the non-repeating part (21). Multiply both sides by 10⁵ = 100000.

100000 × n = 1821285.285 (equation 2)

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

100000 × n = 1821285.285
   100 × n = 18.21285
 99900 × n = 1819464

181946499900 could be the answer, but it still can be put in the simplest form, i.e., reduced.

To simplify this fraction, divide the numerator and denominator by 12 (the GCF - greatest common factor).

n = 181946499900 = 1819464 ÷ 1299900 ÷ 12 = 1516228325. So,

18.21285 = 1516228325 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 1516228325 is also equal to 1817728325 when expressed as a mixed number.

The repeating decimal 18.21285 (vinculum notation) has a repeated block length of 3. It is also represented as 18.21285285285... (ellipsis notation) which equals approximately 18.21285285285285285 (decimal approximation)(*).

The recurring decimal 18.21285 can be written as a ratio of two integers having 151622 as the numerator and 8325 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.