se 100 combines that are to mbine is a replaceable blade time the order is placed for later time because a special pro- has on the sensitivity of UP. 37. A large national producer of canned foods plans to purchase 100 combin be customized for its needs. One of the parts used in the combine is a ren for harvesting corn. Spare blades can be purchased at the time the order i $100 each, but will cost $1,000 each if purchased at a later time because duction run will be required. It is estimated that the number of replacement blades required by a co its useful lifetime can be closely approximated by a normal distribut 18 and standard deviation 5.2. The combine maker agrees to buy back unus blades for $20 each. How many spare blades should the company purch the combines? required by a combine over mal distribution with