A monkey is trying to climb up a pole of height 20 meters. Every minute the monkey climbs up by 3 meters and in the next 30 seconds it slips down by 1 meter. In how much time will it reach the top of the pole if initially the monkey was at the bottom of the pole?

Rohan walks around a circular field at the rate of 1 round per hour while Shreyas runs around it at the rate of 5 rounds per hour. They start in the same direction from the same point at 8:30 AM. When will they first cross each other?

In covering 90 km, R takes 4 hours more than S. If R triples his speed, then he would take 2 hours less than S. What is R's original speed (in km/h)?