To convert the repeating decimal \(0.123123123...\) into a fraction, we can follow these steps:
- Let \(x = 0.123123123...\).
- Since the decimal repeats every three digits, we can multiply \(x\) by 1000 to shift the decimal point three places to the right: \[ 1000x = 123.123123123... \]
- Now we have two equations: \[ x = 0.123123123... \] \[ 1000x = 123.123123123... \]
- Subtract the first equation from the second: \[ 1000x - x = 123.123123123... - 0.123123123... \] \[ 999x = 123 \]
- Now, solve for \(x\): \[ x = \frac{123}{999} \]
- Now, we can simplify \( \frac{123}{999} \): \[ \frac{123 \div 123}{999 \div 123} = \frac{1}{9} \]
Hence, in its simplest form, the answer is \( \frac{123}{999} \).
So the answer is:
123/999