Using the t test statistic, the value of the test statistic is 1.25.
In the given question we have to find the value of the test statistic.
A manufacturer of chocolate potato chips would like to know whether its bag filling machine works correctly at the 400 gram setting.
= 400
A 25 bag sample had a mean of 399 grams and the variance is 400.
There is sufficient evidence at the 0.025 level that the bags are underfilled.
Sample size(n) = 25
sample Mean = 399
Sample Variance = 400
Standard Deviation = √Sample Variance
Standard Deviation = √400
Standard Deviation = 20
Population Mean = 400
So , the null and alternative hypothesis are
H0 : μ = 400
Ha : μ < 400
Using the sample t test statistic
t = (Population Mean - Sample Mean)/(Standard Deviation/Sample size)
t = (400 - 399)/(20/25)
t = 1*25/20
t = 1.25
To learn more about null and alternative hypothesis link is here
brainly.com/question/27335001
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