Question

An excellent swimmer is confident he can judge his speed in the water exactly. He bets he can swim two lengths of a 50-meter Olympic size pool at an average speed of precisely 2 meters per second. On his first lane he is a little bit slow and ends up going at 1.5 meters per second. Which average speed does he have to reach on his second lane to win the bet?

Answer 1

The time needed at 2 meters per second for both rounds would be 100/2 s or 50 seconds. For the first lane he already used 50/1.5 -> 33.33 seconds, so he would need to cover the other 50 meters in exactly 16.67. 50m divided by the 16.67 seconds he has left means he has to swim at a speed of 3 meters per second.