Making sense of unit conversions 

The goal 
Our goal is to be able to solve problems reliably in all areas in which mathematics is useful for problem solving. Unit conversion not only has many practical, everyday uses but very simply illustrates the problem solving process. 
Problem solving is a natural process 
Before proceeding with examples of unit conversion it is helpful to recall the basic ideas.
First let us keep foremost in our minds that problem solving is a natural process. We are born problem solvers. With this in mind we can readily sense situations in which we are flailing at a problem or receive instruction in problem solving which contradicts the natural problem solving process. 
The definition 
A second important aspect of problem solving is simply the definition of a problem. Being aware of what a problem is helps one avoid flailing.
A problem is a request for a result subject to one or more conditions that must be simultaneously satisfied. 
Figure 8.1 

See the simplicity 
Look past the simplicity of the problem to the simplicity of the solution. It is a straight forward application of RequestResponseResult. We will move on to less familiar words and ideas. Yet the process of effecting the unit conversion will remain the same. 
Pay attention to the process 
To illustrate this let's look at converting rood to square feet. 
Figure 8.2 

START WITH WHAT IS ASKED FOR 
The following conversion problem contains two words, township and hectare that may be unfamiliar to you. Don't let this kind of confusion factor stop you from starting the problem solution. The problem asks for an area the is one quarter of a township. You do not need to know what a township is to write the starting equation. Once this is written the equation asks for information about township. There is a large number of sources for this information. 
Figure 8.3 

Need to know 
Information about hectare was not needed till near the end of the solution. The equations will tell you when you need to know something. Simply respond to what the equations ask for by supplying the information requested on a need to know basis. Obtaining the information may require researching various sources such as dictionaries, encyclopedia, the internet, text books, reference books, the literature and so fourth 
Patience! Patience! Patience! 
To be continued 