A manufacturer of potato chips would like to know whether its bag filling machine works correctly at the 423 gram setting. It is believed that the machine is underfilling the bags. A 12 bag sample had a mean of 417 grams with a standard deviation of 27. A level of significance of 0.05 will be used. Assume the population distribution is approximately normal. Determine the decision rule for rejecting the null hypothesis. Round your answer to three decimal places.