Efficient information learning and the interdependence of learning and problem solving was dealt with in Chapter 3. You must now focus on the other blade of the scissors, the mental operations which facilitate efficient application of relevant information to problems. As has been noted, many of the operations used in efficient learning are similar to those which increase effectiveness in problem solving. In learning a new concept like investment trust, for example, you try to identify its features and consider whether some of these are similar to a more familiar concept - such as unit trust. Similarly, you look for features of problems, and use these features to match the new problem to tasks you have successfully completed in the hope that some of the previously used operations can be used in the current problem. This means that the 'dual focus' instructional approach is equally applicable to teaching learners to apply information efficiently to solve problems. The interaction between learning and problem solving is such that, in the process of producing solutions, you often also enhance your mental repertoires, thereby increasing your effectiveness to act on the world.