A truck covers a distance of 550 metres in one minute where as a bus covers a distance of 33 km in 3/4 hours. Then the ratio of their speeds is

Distance covered by truck in 1 minute = 550 m = $$\frac{550}{1000}=\frac{11}{20}$$ km

Time taken by bus = $$\frac{3}{4} \times 60=45$$ minutes

Distance covered by bus in 45 minutes = 33 km

Thus, distance covered in 1 minute = $$\frac{33}{45}=\frac{11}{15}$$ km

$$\therefore$$ Ratio of speeds of trucks and bus

= $$\frac{11}{20} \div \frac{11}{15}$$

= $$\frac{11}{20} \times \frac{15}{11}=\frac{15}{20}$$

= $$\frac{3}{4}$$ = 3 : 4

=> Ans - (C)