1. The problem is to evaluate the expression $20 + 20 \div 2 \times 0 + 5$ without using a calculator. 2. According to the order of operations (PEMDAS/BODMAS), division and multiplication are performed before addition. 3. First, calculate the division: $20 \div 2 = 10$. 4. Next, multiply the result by 0: $10 \times 0 = 0$. 5. Now substitute back into the expression: $20 + 0 + 5$. 6. Finally, perform the addition: $20 + 0 + 5 = 25$. The final answer is $25$.