1 Evaluate without using a calculator: 4x(5-20) 3.1.1 5x(-3+7) + 20 ÷ (-4) 3.1.2 V25 - V8 + V125 3.1.3 3.1.4 16,014 + 2,45 - 0,4 (round your answer correct to 2 decimal places) 3.2 3.3 3,45 x 2,7 3.4 1,450 ÷ 5

$$4 \times (-15) = -60$$

The final answer is $\boxed{-60}$.

3.1.2

$$5 \times 4 = 20$$ $$20 \div (-4) = -5$$

$$20 + (-5) = 15$$

The final answer is $\boxed{15}$.

3.1.3

$$\sqrt{25} = 5$$ $$\sqrt[3]{8} = 2$$ $$\sqrt[3]{125} = 5$$

$$5 - 2 + 5 = 3 + 5 = 8$$

The final answer is $\boxed{8}$.

3.1.4

$$\sqrt[3]{-\frac{3}{8}} = \frac{\sqrt[3]{-3}}{\sqrt[3]{8}}$$

Since $\sqrt[3]{-3}$ is not a rational number, and the problem asks to evaluate, it implies a simplification if possible. However, the expression is $\sqrt[3]{-\frac{3}{8}}$.
We can write $\sqrt[3]{-\frac{3}{8}} = \sqrt[3]{-1 \times \frac{3}{8}} = \sqrt[3]{-1} \times \sqrt[3]{\frac{3}{8}} = -1 \times \frac{\sqrt[3]{3}}{\sqrt[3]{8}}$

$$= -1 \times \frac{\sqrt[3]{3}}{2} = -\frac{\sqrt[3]{3}}{2}$$

The final answer is $\boxed{-\frac{\sqrt[3]{3}}{2}}$.

3.2

The third decimal place is 4, which is less than 5, so we round down.

$$18.064 \approx 18.06$$

The final answer is $\boxed{18.06}$.

3.3

$$3.45 \times 2.7$$

Multiply $345 \times 27$:
$345 \times 7 = 2415$
$345 \times 20 = 6900$
$2415 + 6900 = 9315$
Since there are a total of $2+1=3$ decimal places in 3.45 and 2.7, place the decimal point 3 places from the right in the product.

$$3.45 \times 2.7 = 9.315$$

The final answer is $\boxed{9.315}$.

3.4

$$1450 \div 5$$ $$1450 \div 5 = 290$$

The final answer is $\boxed{290}$.