$r=\frac{\operatorname{sen}^{3} 30^{\circ}}{\left(\cos 30^{\circ}\right)}+\frac{3 \cdot \operatorname{sen} 20^{\circ}+\cos 40^{\circ}}{\cos 60^{\circ}}$

Step 1 ：\(\sin 30^\circ = 0.5\)

Step 2 ：\(\cos 30^\circ = \frac{\sqrt{3}}{2}\)

Step 3 ：\(\sin 20^\circ = 0.342\)

Step 4 ：\(\cos 40^\circ = 0.766\)

Step 5 ：\(\cos 60^\circ = \frac{1}{2}\)

Step 6 ：\(r = \frac{0.5^3}{\frac{\sqrt{3}}{2}} + \frac{3 \cdot 0.342 + 0.766}{\frac{1}{2}}\)

Step 7 ：\(r = \frac{0.125}{\frac{\sqrt{3}}{2}} + \frac{3 \cdot 0.342 + 0.766}{\frac{1}{2}}\)

Step 8 ：\(r = \frac{0.125 \cdot 2}{\sqrt{3}} + 2(3 \cdot 0.342 + 0.766)\)

Step 9 ：\(r = \frac{0.25}{\sqrt{3}} + 2(1.026 + 0.766)\)

Step 10 ：\(r = \frac{0.25}{\sqrt{3}} + 2(1.792)\)

Step 11 ：\(r = \frac{0.25}{\sqrt{3}} + 3.584\)

Step 12 ：\(\boxed{r \approx 3.729}\)