What is 1.2799999... as a Fraction?

1.279 equals 3225 as a fraction.

How do you turn 1.279 repeating into a fraction?

Detailed Answer:

Step 1: To convert 1.279 repeating into a fraction, begin writing this simple equation:

n = 1.279 (equation 1)

Step 2: Notice that there is 1 digit in the repeating block (9) and 2 digits in the non-repeating part (27). Multiply both sides by 10³ = 1000.

1000 × n = 1279.9 (equation 2)

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

1000 × n = 1279.9
 100 × n = 1.279
 900 × n = 1152

1152900 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 36 (the GCF - greatest common factor).

n = 1152900 = 1152 ÷ 36900 ÷ 36 = 3225. So,

1.279 = 3225 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 3225 is also equal to 1725 when expressed as a mixed number.

The repeating decimal 1.279 (vinculum notation) has a repeated block length of 1. It is also represented as 1.27999... (ellipsis notation) which equals approximately 1.2799999 (decimal approximation)(*).

The recurring decimal 1.279 can be written as a ratio of two integers having 32 as the numerator and 25 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.