Short Answer 
To calculate total expenses from 2009 to 2011, first identify the annual expenses: 100 (2009), 150 (2010), and 200 (2011). Adding these gives a total of 450, which is essential for assessing financial performance during this period.
Step 1: Identify the Annual Expenses
To calculate the total expenses from 2009 to 2011, first, we need to extract the annual expenses for each year. The data shows the following amounts:
- 2009: 100
- 2010: 150
- 2011: 200
Step 2: Add the Annual Expenses
Next, we will add these annual expenses together to get the total. This calculation is crucial as it forms the basis for understanding overall spending during this period:
- 100 (2009)
- + 150 (2010)
- + 200 (2011)
Step 3: Calculate the Total Expenses
Finally, by summing these figures, we can arrive at the total expenses for the period from 2009 to 2011. The sum can be expressed as:
- Total Expenses = 100 + 150 + 200 = 450
This total helps to assess overall financial performance across the years considered.