To solve this problem, we solve for the z score of
proportions. Using the formula:
z = (p1 – p2) / sqrt [(p2 (1 – p2) / n)]
where,
p1 = 0.04
p2 = 0.02
n = 50
Therefore:
z = (0.04 – 0.02) / sqrt [(0.02 (1 – 0.02) / 50)]
z = 1.01
From the standard probabilities table, the p value for
this right tailed test at z = 1.01 is:
P = 0.1562
Therefore there is a probability of 0.1562 or 15.62% that
the nonconforming would be 0.04 and above
