Answer:
The salmon size is less than equal to 10.28 inches represent bottom 25% of all salmon.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 12.5 inches
Standard Deviation, σ = 3.3
We are given that the distribution of salmon size is a bell shaped distribution that is a normal distribution.
Formula:
[tex]z_{score} = \displaystyle\frac{x-\mu}{\sigma}[/tex]
We have to find the value of x such that the probability is 0.25
[tex]P( X < x) = P( z < \displaystyle\frac{x - 12.5}{3.3})=0.25[/tex]
Calculation the value from standard normal z table, we have,
[tex]\displaystyle\frac{x - 12.5}{3.3} = -0.674\\\\x = 10.2758\approx 10.28[/tex]
Thus, the salmon size is equal to or less than 10.28 inches, they are considered small and young and represent bottom 25% of all salmon.