To convert the repeating decimal \(0.27\overline{27}\) to a rational number, we can use the following steps:
Let \(x = 0.27\overline{27}\).
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Identify the repeating part: The decimal repeats every two digits ("27"). So, we can express \(x\) in terms of its repeating part.
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Multiply by a power of 10: To eliminate the repeating part, we can multiply \(x\) by \(100\) (because the repeat is 2 digits). \[ 100x = 27.\overline{27} \]
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Set up the equation: Now we also write the original \(x\) aligned with the new equation: \[ 100x = 27.\overline{27} \] \[ x = 0.27\overline{27} \]
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Subtract the two equations: \[ 100x - x = 27.\overline{27} - 0.27\overline{27} \] \[ 99x = 27 \]
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Solve for \(x\): \[ x = \frac{27}{99} \]
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Simplify the fraction: The greatest common divisor of 27 and 99 is 9. \[ x = \frac{27 \div 9}{99 \div 9} = \frac{3}{11} \]
Thus, the repeating decimal \(0.27\overline{27}\) can be expressed as the rational number
\(\frac{3}{11}\).
Therefore, the answer is
\(\boxed{\frac{3}{11}}\).