Question

A biologist takes a sample of 80 fish from a stream, and 72 of the fish are rainbow trout.
What percentage of the fish are rainbow trout?


? = 11%

? = 72%

? = 90%

? = 8%

Answer 1

To find the percentage of rainbow trout in the sample, you can use the formula:

\[
\text{Percentage} = \left( \frac{\text{Number of rainbow trout}}{\text{Total number of fish}} \right) \times 100
\]

In this case, the number of rainbow trout is 72, and the total number of fish is 80. Plugging in the values:

\[
\text{Percentage} = \left( \frac{72}{80} \right) \times 100
\]

\[
\text{Percentage} = 0.9 \times 100
\]

\[
\text{Percentage} = 90\%
\]

Therefore, the percentage of the fish that are rainbow trout is **90%**.