To convert 0.72 into a fraction, follow these steps:
1. **Write down the decimal divided by 1:**
\[ 0.72 = \frac{0.72}{1} \]
2. **Multiply both the numerator and the denominator by 100** (since there are two digits after the decimal point):
\[ \frac{0.72 \times 100}{1 \times 100} = \frac{72}{100} \]
3. **Simplify the fraction** by finding the greatest common divisor (GCD) of 72 and 100. The GCD of 72 and 100 is 4.
4. **Divide both the numerator and the denominator by the GCD:**
\[ \frac{72 \div 4}{100 \div 4} = \frac{18}{25} \]
So, 0.72 as a fraction is \[ \frac{18}{25} \].