Scientists want to estimate the mean weight of mice after they have been fed a special diet. From previous studies, it is known that the weight is normally distributed with standard deviation 5 grams. How many mice must be weighed so that a 95% confidence interval will have margin of error of 0.6 grams?

Respuesta :

Answer: n = 267

Step-by-step explanation: Margin of Error shows the percentage that will differ the result you get from the real population value or, in other words, is the range of values in a confidence interval.

It can be calculated as

margin of error = [tex]z\frac{s}{\sqrt{n} }[/tex]

in which

z is z-score related to the confidence interval, which is this case is 1.96;

s is standard deviation;

n is the number in a sample;

So, the number of mice must be:

margin of error = [tex]z\frac{s}{\sqrt{n} }[/tex]

[tex]0.6=1.96\frac{5}{\sqrt{n} }[/tex]

[tex]\sqrt{n}=\frac{1.96*5}{0.6}[/tex]

[tex]\sqrt{n}=16.33[/tex]

n = 267

For the margin of error with 95% confidence interval be 0.6, it is needed 267 mice.

The total number of mice must be weighed so that a 95% confidence interval will have a margin of error of 0.6 grams is 267 and this can be determined by using the formula of margin of error.

Given :

  • Scientists want to estimate the mean weight of mice after they have been fed a special diet.
  • From previous studies, it is known that the weight is normally distributed with a standard deviation of 5 grams.
  • 95% confidence interval.

The formula of margin of error can be used in order to determine the total number of mice. The formula of margin of error is given by:

[tex]\rm MOE = z\dfrac{s}{\sqrt{n} }[/tex]

where z is the z-score, s is the standard deviation, and n is the sample size.

Now, substitute the known values in the above formula.

[tex]\rm 0.6 = 1.96\times \dfrac{5}{\sqrt{n} }[/tex]

Simplify the above expression in order to determine the value of 'n'.

[tex]\rm n =\left(\dfrac{1.96\times 5}{0.6}\right)^2[/tex]

n = 267

Therefore, the total number of mice must be weighed so that a 95% confidence interval will have a margin of error of 0.6 grams is 267.

For more information, refer to the link given below:

https://brainly.com/question/20982963

Otras preguntas