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? Show your work and write a sentence to explain what your answer means.(4 points)

1 answer

To find out how long it will take for the fish to reach a depth of -37.8 meters, we start with the initial depth of -10.8 meters and determine how much deeper the fish needs to descend.

  1. Calculate the total depth change needed:

    \[ \text{Depth change} = \text{Final depth} - \text{Initial depth} \] \[ \text{Depth change} = -37.8 - (-10.8) = -37.8 + 10.8 = -27.0 , \text{meters} \]

    The fish needs to descend a total of 27.0 meters.

  2. Determine how much the fish descends every 2 minutes:

    The fish descends 1.5 meters every 2 minutes.

  3. Calculate the total time required to descend 27.0 meters:

    We can find the time by dividing the total depth change needed by the distance descended every 2 minutes.

    First, find how many 1.5 meter intervals are in 27.0 meters:

    \[ \text{Number of intervals} = \frac{27.0 , \text{meters}}{1.5 , \text{meters}} = 18 \]

    Each interval takes 2 minutes, so:

    \[ \text{Total time} = \text{Number of intervals} \times \text{Time per interval} \] \[ \text{Total time} = 18 \times 2 , \text{minutes} = 36 , \text{minutes} \]

Conclusion:

It will take the fish 36 minutes to reach a depth of -37.8 meters from its current position at -10.8 meters. This means that the fish will continue to swim deeper below sea level for a total of 36 minutes until it reaches the target depth.