Chapter 10: “Posing Problems Properly.” In this selection from NCTM’s Forty-second Yearbook (1980), Thomas Butts presents the following types of problems: recognition exercises, algorithmic exercises, application problems, open-search problems, and problem situations. He then addresses the neglected art of problem posing. Please note: This product can only be purchased via NCTM’s Online catalog. Non-web payment methods, such as POs, cannot be used to purchase this item. If you have any questions please call NCTM’s Customer Service Department at 800-235-7566.