Understanding the Population Data Table

The question provides a table showing the population of three cities, P, Q, and R, over seven years, from 2014 to 2020. The population is given in lakhs. We are asked to find the difference between the total population of City-R and the total population of City-Q across all these seven years.

Calculating Total Population of City-R

To find the total population of City-R over the seven years (2014 to 2020), we need to sum up the population of City-R for each individual year.

Total Population of City-R $= \text{Population in } 2014 + \text{Population in } 2015 + \text{Population in } 2016 + \text{Population in } 2017 + \text{Population in } 2018 + \text{Population in } 2019 + \text{Population in } 2020$

Using the data from the table:

Total Population of City-R $= 50 + 40 + 60 + 70 + 80 + 90 + 100$

Total Population of City-R $= 490$ Lakhs

Calculating Total Population of City-Q

Similarly, to find the total population of City-Q over the seven years (2014 to 2020), we sum up the population of City-Q for each year.

Total Population of City-Q $= \text{Population in } 2014 + \text{Population in } 2015 + \text{Population in } 2016 + \text{Population in } 2017 + \text{Population in } 2018 + \text{Population in } 2019 + \text{Population in } 2020$

Using the data from the table:

Total Population of City-Q $= 20 + 30 + 50 + 55 + 60 + 70 + 75$

Total Population of City-Q $= 360$ Lakhs

Finding the Difference in Total Population

The question asks for the difference in the total population of City-R and the total population of City-Q for all seven years. This means we subtract the total population of City-Q from the total population of City-R.

Difference $= \text{Total Population of City-R} - \text{Total Population of City-Q}$

Difference $= 490 \text{ Lakhs} - 360 \text{ Lakhs}$

Difference $= 130 \text{ Lakhs}$

Summary of Calculations

• Total Population of City-R: $50 + 40 + 60 + 70 + 80 + 90 + 100 = 490$ Lakhs
• Total Population of City-Q: $20 + 30 + 50 + 55 + 60 + 70 + 75 = 360$ Lakhs
• Difference: $490 - 360 = 130$ Lakhs

The difference in the total population of City-R and the total population of City-Q for all seven years is 130 Lakhs.

Revision Table: Key Concepts for Population Data Analysis

Additional Information: Working with Population Data

Population data presented in tables can be used for various analyses beyond just finding totals and differences. Some common analyses include:

• Finding Averages: Calculate the average population of a city over a period. For example, average population of City P from 2014-2020 would be $(40+45+60+50+70+65+80)/7$.
• Calculating Growth Rate: Determine how much the population of a city increased or decreased between two years, often expressed as a percentage. Growth Rate $= \frac{\text{Population}_\text{Later Year} - \text{Population}_\text{Earlier Year}}{\text{Population}_\text{Earlier Year}} \times 100\%$.
• Comparing Trends: Observe if the population of different cities is increasing, decreasing, or staying stable over time and compare their patterns. For instance, City R shows a generally increasing trend.
• Finding Maximum/Minimum: Identify the year with the highest or lowest population for a specific city. For example, City R had its lowest population in 2015 (40 Lakhs) and highest in 2020 (100 Lakhs).

Understanding how to extract information and perform basic calculations like summation and difference is fundamental to interpreting tabular data.