In an effort to the reduce budget in the Navy Southwest Region, Naval Facilities Engineering Command (NAVFAC) proposed to pool certain inventories among Naval bases that are located within short distance. NAVBASEs Coronado, Point Loma and San Diego were considered prime candidate locations for the inventory improvement initiative. They identified a type of valve for which the lead time demand has the following distributions:
mean std dev
Coronado 21 9
San Diego 25 11
Point Loma 12 4.8
Question:
What is the coefficient of variance of the combined demand?