Analyzing COVID-19 Affected Persons and Male-Female Ratios

The question asks us to determine the percentage difference in the number of male persons affected by 'COVID-19' in City 'B' compared to City 'A'. We are given a table with the total number of affected persons in thousands for five cities and the ratio of affected male to female for each city.

Calculating Affected Males in City A and City B

To find the percentage difference, we first need to calculate the actual number of affected male persons in both City 'A' and City 'B'.

Step 1: Calculate the number of affected males in City 'A'.

• Total affected persons in City A = 64,000
• Ratio of Male : Female in City A = 5 : 3
• Total ratio parts for City A = \(5 + 3 = 8\)
• Fraction of males in City A = \(\frac{\text{Male Ratio Part}}{\text{Total Ratio Parts}} = \frac{5}{8}\)
• Number of affected males in City A = \(\text{Total Affected} \times \text{Male Fraction}\)
• Number of affected males in City A = \(64,000 \times \frac{5}{8}\)
• Number of affected males in City A = \(8,000 \times 5 = 40,000\)

Step 2: Calculate the number of affected males in City 'B'.

• Total affected persons in City B = 54,000
• Ratio of Male : Female in City B = 5 : 4
• Total ratio parts for City B = \(5 + 4 = 9\)
• Fraction of males in City B = \(\frac{\text{Male Ratio Part}}{\text{Total Ratio Parts}} = \frac{5}{9}\)
• Number of affected males in City B = \(\text{Total Affected} \times \text{Male Fraction}\)
• Number of affected males in City B = \(54,000 \times \frac{5}{9}\)
• Number of affected males in City B = \(6,000 \times 5 = 30,000\)

Calculating Percentage Difference

Now that we have the number of affected male persons in both cities, we can calculate the percentage difference. We need to find by what percentage the number of affected males in City 'B' is more or less than that in City 'A'.

Step 3: Calculate the percentage difference.

• Number of affected males in City B = 30,000
• Number of affected males in City A = 40,000
• Difference in affected males = Number of affected males in City B - Number of affected males in City A
• Difference = \(30,000 - 40,000 = -10,000\)
• Since the difference is negative, the number of affected males in City B is less than in City A.
• Percentage difference (less) = \(\frac{\text{Difference}}{\text{Number of affected males in City A}} \times 100\%\)
• Percentage difference (less) = \(\frac{40,000 - 30,000}{40,000} \times 100\%\)
• Percentage difference (less) = \(\frac{10,000}{40,000} \times 100\%\)
• Percentage difference (less) = \(\frac{1}{4} \times 100\%\)
• Percentage difference (less) = \(25\%\)

The number of male persons affected by 'COVID-19' in City 'B' is 25% less than that of number of male persons from City 'A'.

Revision Table: COVID-19 Data Analysis

Here is a summary of the key figures calculated for City A and City B:

Additional Information on Ratio and Percentage Calculations

Understanding ratios and percentage differences is crucial for data interpretation questions.

• Ratio: A ratio compares two or more quantities. If a quantity is divided in the ratio \(a:b\), the total parts are \(a+b\). The first part is \(\frac{a}{a+b}\) of the total, and the second part is \(\frac{b}{a+b}\) of the total.
• Percentage Difference: When comparing value A and value B, the percentage difference relative to A is calculated as \(\frac{|\text{B} - \text{A}|}{\text{A}} \times 100\%\). To determine if B is 'more' or 'less' than A, you compare B directly to A. If \(B > A\), it's a percentage increase or 'more'. If \(B < A\), it's a percentage decrease or 'less'. The question specifically asks "what percent more or less than that of City 'A'", meaning City A is the base for the comparison.

These basic concepts help in analyzing data sets and drawing conclusions based on the numbers provided. Practicing with different ratios and percentage calculations will improve speed and accuracy in solving data interpretation problems.