1. **Match each calculation to its correct answer:** - Calculate $3 \times 10^3$: $$3 \times 10^3 = 3 \times 1000 = 3000$$ So, $3 \times 10^3$ matches with 3000. - Calculate $3 \div 10^{-2}$: $$3 \div 10^{-2} = 3 \times 10^2 = 3 \times 100 = 300$$ So, $3 \div 10^{-2}$ matches with 300. - Calculate $3 \div 10^2$: $$3 \div 10^2 = 3 \div 100 = 0.03$$ So, $3 \div 10^2$ matches with 0.03. - Calculate $3 \times 10^{-3}$: $$3 \times 10^{-3} = 3 \times 0.001 = 0.003$$ So, $3 \times 10^{-3}$ matches with 0.003. - The value 0.0003 is not matched with any given expression. 2. **Identify the incorrect statement:** - $x + y - m = x - m + y$ is correct because addition and subtraction are associative and commutative in this context. - $x + a - b = b - a + x$ is incorrect because the right side rearranges terms incorrectly; subtraction is not commutative. - $t \times m \times c = c \times t \times m$ is correct because multiplication is commutative. - $(v + w) \div x = (w + v) \div x$ is correct because addition is commutative. Therefore, the incorrect statement is: $x + a - b = b - a + x$. 3. **Expression for the cost of one bag of flour:** - Given total cost for $n$ bags is $d$. - Cost per bag = total cost divided by number of bags: $$\text{Cost per bag} = \frac{d}{n}$$ **Final answers:** - Matches: - $3 \times 10^3 = 3000$ - $3 \div 10^{-2} = 300$ - $3 \div 10^2 = 0.03$ - $3 \times 10^{-3} = 0.003$ - Incorrect statement: $x + a - b = b - a + x$ - Cost per bag: $\frac{d}{n}$