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According to a census report, the popula...

According to a census report, the population growth rate of Faridabad is going to be an increasing A.P. with first year's rate as 5% and common difference as 5%, but simultaneously the migration rate is an increasing G.P. with first term as 1% and common ratio of 2. If population on 31 December 2010 is 1 million, then find in which year will Faridabad witness its first fall in population?

A

2016

B

2014

C

2013

D

2019

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the population growth rate and the migration rate year by year until we find the year when the population starts to decline. ### Step-by-Step Solution: 1. **Identify the Initial Population and Rates**: - Initial population on December 31, 2010 = 1,000,000. - Population growth rate (increasing A.P.): - First year = 5% - Common difference = 5% - Migration rate (increasing G.P.): - First term = 1% - Common ratio = 2 2. **Calculate the Population Growth Rate for Each Year**: - Year 1 (2011): Growth = 5% - Year 2 (2012): Growth = 5% + 5% = 10% - Year 3 (2013): Growth = 10% + 5% = 15% - Year 4 (2014): Growth = 15% + 5% = 20% - Year 5 (2015): Growth = 20% + 5% = 25% - Year 6 (2016): Growth = 25% + 5% = 30% 3. **Calculate the Migration Rate for Each Year**: - Year 1 (2011): Migration = 1% - Year 2 (2012): Migration = 1% * 2 = 2% - Year 3 (2013): Migration = 2% * 2 = 4% - Year 4 (2014): Migration = 4% * 2 = 8% - Year 5 (2015): Migration = 8% * 2 = 16% - Year 6 (2016): Migration = 16% * 2 = 32% 4. **Calculate the Effective Population Change for Each Year**: - Year 1 (2011): - Population increase = 5% of 1,000,000 = 50,000 - Migration = 1% of 1,000,000 = 10,000 - Net population = 1,000,000 + 50,000 - 10,000 = 1,040,000 - Year 2 (2012): - Population increase = 10% of 1,040,000 = 104,000 - Migration = 2% of 1,040,000 = 20,800 - Net population = 1,040,000 + 104,000 - 20,800 = 1,123,200 - Year 3 (2013): - Population increase = 15% of 1,123,200 = 168,480 - Migration = 4% of 1,123,200 = 44,928 - Net population = 1,123,200 + 168,480 - 44,928 = 1,246,752 - Year 4 (2014): - Population increase = 20% of 1,246,752 = 249,350.4 - Migration = 8% of 1,246,752 = 99,740.16 - Net population = 1,246,752 + 249,350.4 - 99,740.16 = 1,396,362.24 - Year 5 (2015): - Population increase = 25% of 1,396,362.24 = 349,090.56 - Migration = 16% of 1,396,362.24 = 223,417.96 - Net population = 1,396,362.24 + 349,090.56 - 223,417.96 = 1,521,034.84 - Year 6 (2016): - Population increase = 30% of 1,521,034.84 = 456,310.45 - Migration = 32% of 1,521,034.84 = 486,712.74 - Net population = 1,521,034.84 + 456,310.45 - 486,712.74 = 1,490,632.55 5. **Determine the Year of First Population Decline**: - In 2016, the population increase (30%) is less than the migration (32%). Therefore, the first fall in population will occur in the year 2016. ### Final Answer: Faridabad will witness its first fall in population in the year **2016**.
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