Answer:
The probability of selecting a bolt at random that has a diameter larger than 0.328 inches is 0.00256.
Step-by-step explanation:
We are given that the diameters of bolts produced by a certain machine are normally distributed with a mean of 0.30 inches and a standard deviation of 0.01 inches.
<em>Let X = diameters of bolts produced by a certain machine</em>
SO, X ~ N()
The z-score probability distribution is given by ;
Z = ~ N(0,1)
where, = mean diameter = 0.30 inches
= standard deviation = 0.01 inches
The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X.
Now, the probability of selecting a bolt at random that has a diameter larger than 0.328 inches is given by = P(X > 0.328 inches)
P(X > 0.328) = P( > ) = P(Z > 2.80) = 1 - P(Z 2.80)
= 1 - 0.99744 = 0.00256
<em>The above probability is calculated using z table by looking at value of x = 2.80 in the z table which have an area of 0.99744.</em>
Therefore, probability of selecting a bolt at random that has a diameter larger than 0.328 inches is 0.00256.