By using the concept of mean and standard deviation, it can be inferred that
The the drug stays in the system for more than 397 minutes
What is mean and Standard Deviation?
Suppose there is a data set and the average of the data set has to be calculated. To calculate the average of the data set, mean is used
To know about Standard Deviation, it is important to know about Variance
Variance is the sum of the square of deviation from mean.
Square root of the variance gives the standard deviation
Given n = 35,
[tex]\bar{x} = 403,[/tex]
Population mean [tex]\\ (\mu)[/tex] = 397
Population Standard Deviation [tex]\\(\sigma)[/tex] = 18
Here the sample size is large. So the distribution is approximately normal
To test :
[tex]H_ 0 = \mu \leq 397\\H_1 = \mu > 397[/tex]
Test statistic t = [tex]\frac{403 - 397}{\frac{18}{\sqrt{35}}}[/tex]
= 1.97
p value at [tex]\alpha = 0.05[/tex] = 0.0244
Since 0.0244 < 0.05, the null hypothesis is rejected
So the the drug stays in the system for more than 397 minutes
To learn more about mean and Standard Deviation, refer to the link
https://brainly.com/question/28225633
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