A manufacturing process produces bags of chips whose weight is N(16 oz, 1.5 oz). On a given day, the quality control officer takes a sample of 36 bags and computed the mean weight of these bags. The probability that the sample mean weight is below 16 oz isGroup of answer choices:A. 0.55B. 0.45C. 0.50D. 0.60
Accepted Solution
A:
Answer:C. 0.50
Step-by-step explanation:Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean". The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean". Let X the random variable who represent the weight for bags of chips of a population, and for this case we know the distribution for X is given by: n=16 represent the sample size[tex]\mu =16[/tex] represent the true mean[tex]\sigma=1.5[/tex] represent the population standard deviation[tex]X \sim N(16,1.5)[/tex] Where [tex]\mu=16[/tex] and [tex]\sigma=1.5[/tex] And let [tex]\bar X[/tex] represent the sample mean, the distribution for the sample mean is given by: [tex]\bar X \sim N(\mu,\frac{\sigma}{\sqrt{n}})[/tex] The probability that the sample mean weight is below 16 oz is:[tex]P(\bar x<16)=P(Z<\frac{16-16}{\frac{1.5}{\sqrt{36}}})=P(Z<0)=0.5[/tex]
So the best option for this case is 0.5