Using addition of variables, it is found that the mean and approximate standard deviation of the total weight of lobsters Captain Richards traps in a day are given by:
(B) Mean = 22 pounds; Standard deviation = 8.32 pounds.
What is the mean and the standard deviation of the sum of two independent variables?
When two independent variables are added, we have that:
- The mean is the sum of the means.
- The standard deviation is the square root of the sum of the variances.
In this problem:
- The means are of 12 pounds and of 10 pounds.
- The variances, in pounds squared, are of [tex]7^2[/tex] and [tex]4.5^2[/tex], respectively.
Then:
[tex]M = 12 + 10 = 22[/tex]
[tex]S = \sqrt{7^2 + 4.5^2} = 8.32[/tex]
Hence option B is correct.
You can learn more about addition of variables at https://brainly.com/question/25769446