What is the maximum significance level that the null hypothesis is not rejected?
How do I calculate it?
Context:
The weight of a plate is a normally distributed variable with μ=330 gr. and standard deviation σ=5 gr. A sample of 25 plates has a mean weight of 333 gr. Given that the variance is σ^2=25, test the hypothesis that the population mean has increased (or it has remained the same), with a significance level of 10 %. What is the maximum significance level that the null hypothesis is not rejected?