Question

A company produces steel rods. The lengths of the steel rods are normally distributed with a mean of 180.6-cm and a standard deviation of 1-cm. For shipment, 11 steel rods are bundled together. Round all answers to four decimal places if necessary.

What is the distribution of X ? X ~ N( , )

What is the distribution of ¯ x ? ¯ x ~ N( , )

For a single randomly selected steel rod, find the probability that the length is between 180.2-cm and 180.7-cm.

For a bundled of 11 rods, find the probability that the average length is between 180.2-cm and 180.7-cm. For part d), is the assumption of normal necessary? YesNo

Answer 1