A man standing in front of a mountain at a certain distance beats a drum at refular intervals. He increases the beating rate and finds that the echo is not heard distinctly when the rate becomes `40` per minute. He then moves nearer to the mountain by 90 m and finds that the echo is again not heard when the beating rate is 60 per minute. Calculate the velocity of sound and the distance between the mountain and the initial position of the man.

Answer

`360 m s^(-1), 270 m`