Question

An engineer has conducted an experiment on the weight of bags of sugar that come off the filling line. A sample of size 50 is collected, and it is found to have a sample mean of 16.147 lbs and a standard deviation of 0.87 lbs. Calculate the 95% Confidence Interval on the weight of the bags of flour, and use it to determine if it is believable that the population mean for the weight of all bags of flour produced on this line, is equal to 16 lbs

Answer 1

given that

sample size n = 50

sample mean xbar = 16.147

standard deviation s = 0.87

degree of freddom = n-1

= 50-1

= 49

using t distribution table for alpha 0.05 and df(49), we get

t critical = 2.01

CI=

it is clear that the mean value of 16 is included in the confidence interval, therefore, we can say that the population mean for the weight of all bags of flour produced on this line, is equal to 16 lbs