1. The problem is to reduce the fraction $\frac{13}{26}$ to its lowest terms. 2. Find the greatest common divisor (GCD) of 13 and 26. Since 13 is a prime number and divides 26 exactly, $\gcd(13, 26) = 13$. 3. Divide both numerator and denominator by the GCD 13: $$\frac{13 \div 13}{26 \div 13} = \frac{1}{2}$$ 4. The fraction $\frac{13}{26}$ reduced to lowest terms is $\frac{1}{2}$.