An athlete has to cover a distance of 6 Kms in 90 Minutes. He covers two-third of the distance in two-thirds of the total time. To cover the remaining distance in the remaining time, his speed should be____ Km/Hr. ?

Total distance = 6 km, Total time = 90 min = 1.5 hr

Distance covered = $\frac{2}{3}\times6=4$ km, Time taken = $\frac{2}{3}\times90=60$ min = 1 hr

Speed in first part = $\dfrac{4}{1}=4$ km/hr

Remaining distance = 2 km, Remaining time = 0.5 hr

Required speed = $\dfrac{2}{0.5}=4$ km/hr

Answer: $\boxed{4\text{ km/hr}}$ ✅