What is 91.11111... as a Fraction?

91.111 equals 8209 as a fraction.

How do you turn 91.111 repeating into a fraction?

Detailed Answer:

Step 1: To convert 91.111 repeating into a fraction, begin writing this simple equation:

n = 91.111 (equation 1)

Step 2: Notice that there is 1 digit in the repeating block (1) and 2 digits in the non-repeating part (11). Multiply both sides by 10³ = 1000.

1000 × n = 91111.1 (equation 2)

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

1000 × n = 91111.1
 100 × n = 91.111
 900 × n = 82000

82000900 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 100 (the GCF - greatest common factor).

n = 82000900 = 82000 ÷ 100900 ÷ 100 = 8209. So,

91.111 = 8209 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 8209 is also equal to 9119 when expressed as a mixed number.

The repeating decimal 91.111 (vinculum notation) has a repeated block length of 1. It is also represented as 91.11111... (ellipsis notation) which equals approximately 91.1111111 (decimal approximation)(*).

The recurring decimal 91.111 can be written as a ratio of two integers having 820 as the numerator and 9 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.