In: Statistics and Probability
A manufacturer of potato chips would like to know whether its bag filling machine works correctly at the 445-gram setting. It is believed that the machine is underfilling the bags. A 26 bag sample had a mean of 438 grams with a variance of 289. Assume the population is normally distributed. A level of significance of 0.010.01 will be used. Find the P-value of the test statistic. You may write the P-value as a range using interval notation, or as a decimal value rounded to four decimal places.
Null hypothesis
Alternative hypothesis
We have for given sample,
Population mean for given sample=445
Sample mean=438
Sample standard deviation s=17
Sample size =n=26
Degree of freedom = n-1 =25
t test statistic formula is
P value is approximately 0.023 ....................by using Excel command TDIST(-2.1,25,1)
P value is 0.023 > 0.01
Therefore, we fail to reject H0.