Step-by-Step Solution for Converting 0.81 to a Fraction

Step 1: Understand the Number

The number 0.81 is a decimal, which can be broken into two parts:

  • The whole number part is: 0.
  • The decimal part is: 0.81.

We aim to convert the entire number into a fraction.

Step 2: Isolate the Decimal Part (0.81)

Focus on the decimal part (0.81) and represent it as a fraction.

Step 2.1: Write 0.81 as \( \frac81100 \)

The decimal 0.81 can be read as "81 hundredths." Mathematically, this is:

\[ 0.81 = \frac81100 \]

Step 2.2: Simplify the Fraction

Now simplify \( \frac81100 \) by finding the greatest common divisor (GCD) of 81 and 100.

  • The GCD of 81 and 100 is: 1.
  • Therefore, the simplified fraction is:

\[ \frac81100 \]

Step 3: Combine the Whole Number and Fraction

The original number 0.81 is the sum of the whole number 0 and the fraction \( \frac81100 \).

Combine these as a mixed number:

\[ 0.81 = 0 + \frac81100 = \frac81/100 \]

Step 4: Verify the Answer

To verify, divide \( \frac81/100 \):

\[ \frac81/100 = 0.81 \]

Thus, the fraction is correct.

Final Answer

The decimal 0.81 as a fraction is:

\[ \frac81/100 \]

If expressed as a mixed number:

\[ 81/100 \]