To write 4% as a fraction, you start by understanding that "percent" means "per hundred." Therefore, 4% can be written as:
\[ \frac{4}{100} \]
Next, you can simplify the fraction. Both the numerator and denominator can be divided by 4:
\[ \frac{4 \div 4}{100 \div 4} = \frac{1}{25} \]
Thus, 4% as a fraction is:
\[ \frac{1}{25} \]