Answer: 0.01827
Explanation:
Given: The lengths of the red drum species of fish have an approximately Normal distribution, with a mean length
of 24 inches and a standard deviation
of 1.4 inches.
Let x= length of the red drum species of fish
The probability that length is not between 21 and 28 inches long :
![1-P(21<X<28)=1-P((21-24)/(1.4)<(X-\mu)/(\sigma)<(28-24)/(1.4))\\\\=1-P(-2.14<z<2.86)\ \ \ [Z=(X-\mu)/(\sigma)]\\\\=1-(P(z<2.86)-P(z<-2.14))\\\\=1-(0.9979-0.01617)\\\\=1-0.98173=0.01827](https://img.qammunity.org/2021/formulas/mathematics/high-school/no7ise2w94o0g0lixlls2i69wtek1q839r.png)
Hence, the proportion of red drum fish must be thrown back = 0.01827