What is 12.20428428428... as a Fraction?

12.20428 equals 30480224975 as a fraction.

How do you turn 12.20428 repeating into a fraction?

Detailed Answer:

Step 1: To convert 12.20428 repeating into a fraction, begin writing this simple equation:

n = 12.20428 (equation 1)

Step 2: Notice that there are 3 digits in the repeating block (428) and 2 digits in the non-repeating part (20). Multiply both sides by 10⁵ = 100000.

100000 × n = 1220428.428 (equation 2)

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

100000 × n = 1220428.428
   100 × n = 12.20428
 99900 × n = 1219208

121920899900 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 4 (the GCF - greatest common factor).

n = 121920899900 = 1219208 ÷ 499900 ÷ 4 = 30480224975. So,

12.20428 = 30480224975 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 30480224975 is also equal to 12510224975 when expressed as a mixed number.

The repeating decimal 12.20428 (vinculum notation) has a repeated block length of 3. It is also represented as 12.20428428428... (ellipsis notation) which equals approximately 12.20428428428428428 (decimal approximation)(*).

The recurring decimal 12.20428 can be written as a ratio of two integers having 304802 as the numerator and 24975 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.