1. The problem is to simplify the expression $1 - \frac{3}{4}$. 2. To subtract a fraction from a whole number, convert the whole number to a fraction with the same denominator: $1 = \frac{4}{4}$. 3. Now subtract the fractions: $$\frac{4}{4} - \frac{3}{4} = \frac{4-3}{4} = \frac{1}{4}.$$ 4. The simplified result is $\frac{1}{4}$. Therefore, $1 - \frac{3}{4} = \frac{1}{4}$.