A fish is swimming at −10.8 meters, or 10.8 meters below sea level. Every 2 minutes it descends another 1.5 meters. How long will it take for the fish to reach a depth of -37.8 meters?

Answer 1

The fish descends 1.5 meters every 2 minutes, so the number of 1.5 meter increments it takes to reach the desired depth is -37.8 meters / 1.5 meters = <<37.8/1.5=25.2>>25.2 increments.
Since each increment takes 2 minutes, the fish will take a total of 25.2 increments * 2 minutes/increment = <<25.2*2=50.4>>50.4 minutes to reach a depth of -37.8 meters. Answer: \boxed{50.4}.