A and B start travelling in opposite direction starting from the same spot. A travels at a speed of 65.8 kmph and B is travelling at a spee…

Since, they walk in the opposite direction, relative speed = 65.8 + 56.4 = 122.2 kmph

Distance between them in one hour is 122.2 km

Distance between them after 3 hours 20 minutes i.e. $(\frac{{10}}{3})$ hours $(= 122.2 \times \frac{{10}}{3} = 407.33)$ km