If a bus travels 160 km in 4 hours and a train travels 320 km in 5 hours at uniform speeds, then the ratio of the distance travelled by them in one hour is:

1. 1 : 2
2. 4 : 5
3. 5 : 8
4. 8 : 5

The correct option is C 5 : 8
Given,
Distance travelled by bus in 4h = 160km
And distance travelled by train in 5h = 320km
The ratio of the distance travelled and time taken to cover that distance is called speed.
$\therefore$ Speed $=\frac{Distance}{Time}$
Hence, speed of bus $=\frac{160}{4}=40km/h$
and speed of train $=\frac{320}{5}=64km/h$
Ratio of speed of bus to that of train $=\frac{40}{64}$
$=\frac{5}{8}$ [on dividing numerator and denominator by 8]
= 5: 8
Hence, (c) is the correct option.