Calculating Percentage Increase in Battery Sales

The question asks for the approximate percentage increase in the sales of 55AH batteries from the year 2015 to the year 2021, based on the provided table showing year-wise battery sales.

Identifying the Relevant Data

First, we need to extract the sales figures for 55AH batteries for the specific years mentioned in the question from the given table.

From the table, we can find the following sales figures for 55AH batteries:

• Sales of 55AH batteries in 2015 = 108 thousand
• Sales of 55AH batteries in 2021 = 145 thousand

Calculating the Percentage Increase

To find the percentage increase, we use the formula:

\(\text{Percentage Increase} = \left( \frac{\text{Final Value} - \text{Initial Value}}{\text{Initial Value}} \right) \times 100\)

In this case:

• Initial Value (Sales in 2015) = 108 thousand
• Final Value (Sales in 2021) = 145 thousand

First, calculate the increase in sales:

\(\text{Increase} = \text{Sales in 2021} - \text{Sales in 2015}\)

\(\text{Increase} = 145 - 108 = 37 \text{ thousand}\)

Now, calculate the percentage increase:

\(\text{Percentage Increase} = \left( \frac{37}{108} \right) \times 100\)

Let's calculate the value:

\(\frac{37}{108} \approx 0.34259\)

\(\text{Percentage Increase} \approx 0.34259 \times 100 \approx 34.259\%\)

We are asked for the approximate percentage increase. Rounding 34.259% to the nearest whole number gives 34%.

Comparing with Options

Let's compare our calculated approximate percentage increase with the given options:

• Option 1: 28%
• Option 2: 31%
• Option 3: 33%
• Option 4: 34%

Our calculated value, approximately 34%, matches Option 4.

Revision Table: Battery Sales Analysis

Additional Information on Percentage Change

Percentage change is a useful way to show how much a quantity has increased or decreased over time. It's expressed as a percentage of the initial value.

• Percentage Increase: Occurs when the final value is greater than the initial value. The formula is \(\left( \frac{\text{Increase}}{\text{Initial Value}} \right) \times 100\).
• Percentage Decrease: Occurs when the final value is less than the initial value. The formula is \(\left( \frac{\text{Decrease}}{\text{Initial Value}} \right) \times 100\).
• The "Initial Value" or "Base Value" is always the value from the starting point of the comparison. In this problem, the starting point is 2015, so the sales figure for 2015 is the initial value.

Understanding how to calculate percentage change is important for analyzing trends and growth in various data sets, such as sales figures, population changes, or economic indicators.