21. A machine is adjusted such that the average weight of the cans of detergent is 300 grams. The distribution of the weight of the cans is normal with s = 10 grams. Because of the many vibrations experienced by the machine it is believed that the average fill weight could vary. Samples of 30 containers are taken at random on a regular basis to check the accuracy of the machine adjustment. The machine is adjusted if the average weight is less than 296.69 or more than 303.31 grams. Calculate the first order error (Type I error).

0,8238

0,1762

0.0350

0,0700

0,9300

0,5762