From the top of a platform, the angle of elevation of a tower was 30 deg. The tower was 45 mts high and the horizontal distance between the platform and the tower was 40√3 m. What was the height of the platform?
A boy walking at the speed of 4 km/hr covers a certain distance in 6 hours 15 minutes. If he covers the same distance by cycle in 5 hours, then what is the speed (in km/hr) of the cycle?