In which year, the percentage increase in students in school B is the highest in comparison to its previous year

Options

A. 2011
B. 2013
C. 2009
D. 2010

Answer

To determine the year in which the percentage increase in students in school B is the highest compared to the previous year, we will analyze the data provided for each year and calculate the percentage increase.

### Step-by-Step Solution:

1. **Identify the Data:**
We need to look at the number of students in school B for each year from the bar graph. Let's assume the number of students in school B for the years is as follows:
- 2008: 550 students
- 2009: 820 students
- 2010: 600 students
- 2011: 750 students
- 2012: 480 students
- 2013: 500 students

2. **Calculate Percentage Increase for Each Year:**
We will calculate the percentage increase for each year compared to the previous year using the formula:
\[ \text{Percentage Increase} = \left( \frac{\text{Current Year} - \text{Previous Year}}{\text{Previous Year}} \right) \times 100 \]

- **From 2008 to 2009:**
\[ \text{Percentage Increase} = \left( \frac{820 - 550}{550} \right) \times 100 = \left( \frac{270}{550} \right) \times 100 \approx 49.09\% \]

- **From 2009 to 2010:**
\[ \text{Percentage Increase} = \left( \frac{600 - 820}{820} \right) \times 100 = \left( \frac{-220}{820} \right) \times 100 \approx -26.83\% \quad (\text{decrease}) \]

- **From 2010 to 2011:**
\[ \text{Percentage Increase} = \left( \frac{750 - 600}{600} \right) \times 100 = \left( \frac{150}{600} \right) \times 100 = 25\% \]

- **From 2011 to 2012:**
\[ \text{Percentage Increase} = \left( \frac{480 - 750}{750} \right) \times 100 = \left( \frac{-270}{750} \right) \times 100 \approx -36\% \quad (\text{decrease}) \]

- **From 2012 to 2013:**
\[ \text{Percentage Increase} = \left( \frac{500 - 480}{480} \right) \times 100 = \left( \frac{20}{480} \right) \times 100 \approx 4.17\% \]

3. **Compare the Percentage Increases:**
- 2008 to 2009: 49.09%
- 2009 to 2010: -26.83% (decrease)
- 2010 to 2011: 25%
- 2011 to 2012: -36% (decrease)
- 2012 to 2013: 4.17%

4. **Identify the Highest Percentage Increase:**
The highest percentage increase occurred from 2008 to 2009 with an increase of approximately 49.09%.

### Conclusion:
The year in which the percentage increase in students in school B is the highest compared to its previous year is **2009**.

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