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The population of a city decreases by
2.3% per year. If this year's population is 363,000 , what will next year's population be, to the nearest individual?
Answer:

The population of a city decreases by $2.3 \%$ per year. If this year's population is $363$ , $000$ , what will next year's population be, to the nearest individual? $\newline$ Answer:

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Exponential growth and decay: word problems

Full solution

Q. The population of a city decreases by

2.3 \%

per year. If this year's population is

363

,

000

, what will next year's population be, to the nearest individual?

\newline

Answer:

Calculate percentage decrease: Determine the percentage decrease in population. The population decreases by $2.3\%$ per year. To find the decrease in population, we need to calculate $2.3\%$ of the current population of $363,000$ .
Calculate decrease: Calculate the decrease in population. $\newline$ $2.3\%$ of $363,000$ is calculated as $(2.3/100) \times 363,000$ . $\newline$ $= 0.023 \times 363,000$ $\newline$ $= 8,349$
Subtract to find next year's population: Subtract the decrease from the current population to find next year's population. $\newline$ Next year's population = Current population - Decrease in population $\newline$ = $363,000 - 8,349$ $\newline$ = $354,651$ $\newline$ However, since we need to round to the nearest individual, we round this number to $354,651$ .

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