To find out how long it will take for the fish to reach a depth of -37.8 meters, we need to determine the number of times it will descend by 1.5 meters.
First, let's calculate the difference between the current depth of the fish (-10.8 meters) and the target depth (-37.8 meters):
Difference = Target Depth - Current Depth
Difference = -37.8 meters - (-10.8 meters)
Difference = -37.8 meters + 10.8 meters
Difference = -27 meters
The fish descends 1.5 meters every 2 minutes. To find out how many times it will descend by 1.5 meters, we divide the total distance by the amount descended in each step:
Number of Descents = Difference / Descend Distance
Number of Descents = -27 meters / 1.5 meters
Number of Descents = -18
Since the fish descends every 2 minutes, it will take -18 times 2 minutes for the fish to reach a depth of -37.8 meters.
Time = Number of Descents * Time per Descent
Time = -18 * 2 minutes
Time = -36 minutes
Therefore, it will take the fish 36 minutes to reach a depth of -37.8 meters.