Many students often struggle with the question "What or how is the best way to choose variables?". One key to solving many math problems is in how the information is represented. We want the variables to convey all the relevant information without being cumbersome to write repeatedly or to understand. The optimal choice of variables:

For example, suppose we have two entrepreneurs, Alexis and Brandon, and we are to compare their revenues at two different times. How would you represent these quantities?

We could label the individuals A and B, and the time periods 1 and 2. We could call the revenues R_A and R_B, but since we are not interested in any other quantities, we can drop the R and just call the revenues A and B, accomplishing 1). Now since we are dealing with two different time periods, we can call Alexis's revenue in the first time period A1, Alexis's revenue in the second time period A2, and so on, so that we have A1, A2, B1, and B2. Now we have variable representation that covers all relevant information, accomplishing 2), but that is not so complex that we need to refer to a key to remember what each variable represented, accomplishing 3).

- Is simple, easy to read, and has no unnecessary baggage,
- Conveys the relevant information,
- Doesn't require a key for you to remember what they represent.

For example, suppose we have two entrepreneurs, Alexis and Brandon, and we are to compare their revenues at two different times. How would you represent these quantities?

We could label the individuals A and B, and the time periods 1 and 2. We could call the revenues R_A and R_B, but since we are not interested in any other quantities, we can drop the R and just call the revenues A and B, accomplishing 1). Now since we are dealing with two different time periods, we can call Alexis's revenue in the first time period A1, Alexis's revenue in the second time period A2, and so on, so that we have A1, A2, B1, and B2. Now we have variable representation that covers all relevant information, accomplishing 2), but that is not so complex that we need to refer to a key to remember what each variable represented, accomplishing 3).