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0580/43 May/Jun 2022, Question 3: Compound Interest

Cambridge IGCSE Mathematics 0580 · Paper 43 (Extended) · Calculator · 13 marks

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The question, in short

Use a table of tiger numbers by country to work out percentages, a simplified ratio, a percentage increase, and a 2010 count, then model bee population growth with P = abˣ to find the count at 7 months.

Summarised in our own words. Use the official paper for the exact wording and any diagrams.

Part (aia) · 1 mark

Find Nepal's tiger count as a percentage of Bangladesh's count using the table values.

  1. 1198 ÷ 106 × 100
  2. 2= 186.79… ≈ 187%

Answer187 or 186.7 to 186.8 or 186 42/53

Part (aib) · 2 marks

Write the ratio Bangladesh : Indonesia : India tiger numbers in simplest form.

  1. 1106 : 371 : 2226
  2. 2Divide by 53: 2 : 7 : 42

Answer2 : 7 : 42

Part (aii) · 2 marks

Find the percentage increase in India's tigers from 2226 to 2967.

  1. 1Increase = 2967 − 2226 = 741
  2. 2741 ÷ 2226 × 100 = 33.28… ≈ 33.3%

Answer33.3 or 33.28 to 33.29

Part (aiii) · 3 marks

Given India's 2014 count is about 30.48% above 2010, find the 2010 count to the nearest integer.

  1. 1Number in 2010 × 1.3048 = 2226
  2. 2Number in 2010 = 2226 ÷ 1.3048 = 1706.0…
  3. 3≈ 1706

Answer1706

Part (b) · 5 marks

With 2000 bees at month 0 and 2662 at month 3, find a and b in P = abˣ, then the population at 7 months to the nearest integer.

  1. 1x = 0: P = a × b⁰ = a, so a = 2000
  2. 2x = 3: 2000b³ = 2662, b³ = 1.331, b = ∛1.331 = 1.1
  3. 3x = 7: P = 2000 × 1.1⁷ = 3897.43…
  4. 4≈ 3897

Answer3897

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Also searched as: 0580/43/M/J/22 · 0580_s22_qp_43 · 0580 s22 43 · question 3.
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