A town of 40,000 people grows by 5% each year, but at the end of each year, after the growth, 1,000 people move away. What is the population after 2 years?

42,000Correct answerYour answer42,050Correct answerYour answer42,100Correct answerYour answer44,100Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer B

Correct answer: B

Year 1: $40000 \times 1.05 = 42{,}000$ ; minus $1{,}000 = 41{,}000$ .
Year 2: $41000 \times 1.05 = 43{,}050$ ; minus $1{,}000 = 42{,}050$ .

Worth noting

Growing 40,000 for two years first (44,100) and then subtracting 2,000 gives 42,100 — wrong, because the people who left in year 1 do not grow in year 2.

Concept: Compound growth with a fixed yearly outflow
Typical timeTypical: 120 s
Your timeYours: —

The rule this testsPopulation growth and depreciation

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Ten questions from Percentages, at your own pace.

A town of 40,000 people grows by 5% each year, but at the end of each year, after the growth, 1,000 people move away. What is the population after 2 years?

Explanation