1. **State the problem:** (a) Double the sum of 8 and 3. (b) The difference between 16 and 3 is multiplied by 4. Calculate the answers to the additions: -3 + (-1) and -5 + (-4). Also, evaluate the expressions: 24 - 48 \div 4 and 56 + 20 \div (2 + 3). 2. **Write expressions:** (a) Double the sum of 8 and 3 means $2 \times (8 + 3)$. (b) The difference between 16 and 3 multiplied by 4 means $(16 - 3) \times 4$. Additions are $-3 + (-1)$ and $-5 + (-4)$. Expressions to evaluate: $24 - 48 \div 4$ and $56 + 20 \div (2 + 3)$. 3. **Calculate each step:** (a) Calculate sum inside parentheses: $8 + 3 = 11$. Then double it: $2 \times 11 = 22$. (b) Calculate difference: $16 - 3 = 13$. Multiply by 4: $13 \times 4 = 52$. Additions: $-3 + (-1) = -3 - 1 = -4$. $-5 + (-4) = -5 - 4 = -9$. Evaluate expressions: First, division in $24 - 48 \div 4$: $48 \div 4 = 12$. Then subtraction: $24 - 12 = 12$. For $56 + 20 \div (2 + 3)$: Calculate inside parentheses: $2 + 3 = 5$. Divide: $20 \div 5 = 4$. Add: $56 + 4 = 60$. 4. **Final answers:** (a) 22 (b) 52 Additions: -4 and -9 Expressions: 12 and 60