Chapter 5.1, Problem 5.6E

(a)

To determine

To compute an estimate of the total number of fish in the lake.

Answer to Problem 5.6E

There are approximately 150 fish.

Explanation of Solution

We will calculate this by using the equation of capture-recapture method:

  $N=\frac{MT}{R}$

Where $N$ is the size of the population, $M$ is the number of initially marked organism, $T$ is the total in the second sample and $R$ is the marked organism in the recapture.

Thus, we have,

  $\begin{array}{l}N=\frac{MT}{R}\\ =\frac{50\times 75}{25}\\ =150\end{array}$

There are approximately 150 fish.

(b)

To determine

To identify that is the number of fish you calculated in part (a) is definitely, probably, probably not, or definitely not equal to the actual number of fish in the lake and explain.

Answer to Problem 5.6E

Probably not equal to.

Explanation of Solution

The number of fish you calculated in part (a) is probably notequal to the actual number of fish in the lake. This was an estimate, so it is very unlikely that it could predict the exact number of fish in the pond.

(c)

To determine

To explain why the capture-recapture sampling method used in this activity is not biased.

Explanation of Solution

The capture-recapture sampling method used in this activity is not biased because the method in which fish are selected can be assumed to be completely random.