going down: 5/2 seconds
going up: 5/1 seconds
so, down+up = ?
Sadiq dropped his watch into a lake. The depth of the lake is 5 meters. Sadiq can dive down towards the bottom of the lake at a speed of 2 meters per second, but can swim upwards at a rate of 1 meter per second. How long will it take Sadiq to get his watch and return to the surface of the lake?
1 answer