Answer:
a) 18.6%
b) 598,230
Explanation:
a) In the first part of the question, you are given two population values and asked to find the percentage difference between them. A formula you can use for that is ...
percentage difference = (difference)/(original value) × 100%
The difference of interest is the difference between the 2011 population and the 2001 population
difference = 510,000 -430,000 = 80,000
The original value is the 2001 population, so the percentage difference is ...
percentage difference = 80,000/430,000 × 100% = 0.1860 × 100% = 18.6%
This is a positive value, so represents an increase.
The percentage increase in population from 2001 to 2011 was 18.6%.
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b) In the second part, you are given the percentage difference and asked to find the new value. We can rearrange the above formula to find the difference:
difference = (percentage difference)/100% × original value
Then the difference between the 2021 population and the 2011 population will be ...
difference = (17.3%)/100% × 510,000 = 0.173 × 510,000 = 88,230
So, the population in 2021 is expected to be 88,230 more than in 2011:
2021 population = 520,000 +88,230 = 598,230
The predicted population in 2021 is 592,230.