A shirt manufacturer buys cloth by the 100-yard roll from a supplier. For setting up a control chart to manage the irregularities (e.g., loose threads and tears), the following data were collected fro

A shirt manufacturer buys cloth by the 100-yard roll from a supplier. For setting up a control chart to manage the irregularities (e.g., loose threads and tears), the following data were collected from a sample provided by the supplier.

SAMPLE    1   2   3   4   5   6   7   8   9   10

IRREGULARITIES 6   4   3   4   5   5   6   2   4   6

a. Determine the C , Sp, UCL and LCL for a c -chart with z = 2. (Leave no cells blank. Round up any negative LCL value to “0”. Round your answers to 2 decimal places.)

C  4.50

Sp ?

UCL ?

LCL ?

b. Suppose the next five rolls from the supplier had two, two, five, three, and eight irregularities. Is the supplier process under control?

• Yes