Grade 11 Maths · Financial Maths · Paper 1

Compound Interest, Growth and Decay Grade 11

Real Compound Interest, Growth and Decay past paper questions and answers from 2023 to 2025, with each memo split into the ticks examiners give. Try one, mark yourself, and see exactly which skill cost you marks.

past paper questions: 17 past paper questions
skills: 3 skills
videos: 3 videos

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Question 8.1 · November 2025 · Paper 1 · Provincial · 3 marks

8.1 A motorbike costs R250 000 and depreciates by 13% p.a. annually, calculated on the reducing balance method.

Calculate what the motorbike will be worth after 6 years.(3)

Work it out on paper first. Then mark yourself with the official memo, one tick at a time.

Compound Interest, Growth and Decay skills

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More Compound Interest, Growth and Decay Grade 11 questions and answers

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4. Question WE4 · Siyavula Grade 11 Mathematics, 9.2 Simple and compound depreciation, Worked example 4 · 3 marks
WE4 A car is valued at R240 000. If it depreciates at $15%$ p.a. using straight-line depreciation, calculate the value of the car after $5$ years.(3)
Show the memo (3 ticks)Memo
1. ✓
  Formula $P = 240000$ ; $i = 0, 15$ ; $n = 5$
  $A = P (1 - in)$
  1 mark · Calculate depreciation
2. ✓
  Substitution $A = 240000 (1 - 0, 15 \times 5)$
  1 mark · Calculate depreciation
3. ✓
  Answer $A = 240000 (0, 25) = 60000$
  At the end of $5$ years, the car is worth R60 000.
  1 mark · Calculate depreciation
5. Question WE7 · Siyavula Grade 11 Mathematics, 9.2 Simple and compound depreciation, Worked example 7 · 3 marks
WE7 The number of pelicans at the Berg river mouth is decreasing at a compound rate of $12%$ p.a. If there are currently $3200$ pelicans in the wetlands of the Berg river mouth, what will the population be in $5$ years?(3)
Show the memo (3 ticks)Memo
1. ✓
  Formula $P = 3200$ ; $i = 0, 12$ ; $n = 5$
  $A = P (1 - i)^{n}$
  1 mark · Calculate depreciation
2. ✓
  Substitution $A = 3200 (1 - 0, 12)^{5} = 3200 (0, 88)^{5}$
  1 mark · Calculate depreciation
3. ✓
  Answer $A = 1688, 7421 \dots$
  In $5$ years, the pelican population will be approximately $1689$ .
  1 mark · Calculate depreciation
6. Question a · Siyavula Grade 11 Mathematics, 9.2 Simple and compound depreciation, Worked example 8 · 2 marks
A school buys a minibus for R950 000, which depreciates at $13, 5%$ per annum. Determine the value of the minibus after $3$ years if the depreciation is calculated:
a On a straight-line basis.(2)
Show the memo (2 ticks)Memo
1. ✓
  Substitution into simple decay formula $P = 950000$ ; $i = 0, 135$ ; $n = 3$
  $A = P (1 - in)$
  $A = 950000 (1 - 3 \times 0, 135)$
  1 mark · Calculate depreciation
2. ✓
  Answer $A = 950000 (0, 595) = 565250$
  $∴ A = R 565250$
  1 mark · Calculate depreciation
7. Question WE9 · Siyavula Grade 11 Mathematics, 9.2 Simple and compound depreciation, Worked example 9 · 3 marks
WE9 Farmer Jack bought a tractor and it has depreciated by $20%$ p.a. on a reducing-balance basis. If the current value of the tractor is R52 429, calculate how much Farmer Jack paid for his tractor if he bought it $7$ years ago.(3)
Show the memo (3 ticks)Memo
1. ✓
  Formula $A = 52429$ ; $i = 0, 2$ ; $n = 7$
  $A = P (1 - i)^{n}$
  1 mark · Calculate depreciation
2. ✓
  Substitution $52429 = P (1 - 0, 2)^{7} = P (0, 8)^{7}$
  1 mark · Calculate depreciation
3. ✓
  Answer $P = \frac{52 429}{( 0 , 8 ) ^{7}} = 250000, 95 \dots$
  $7$ years ago, Farmer Jack paid R250 000 for his tractor.
  1 mark · Calculate depreciation
8. Question a · Siyavula Grade 12 Mathematics, 3.3 Future value annuities, Worked example 7 · 2 marks
Wellington Courier Company buys a delivery truck for R296 000. The value of the truck depreciates on a reducing-balance basis at $18%$ per annum. The company plans to replace this truck in seven years' time and they expect the price of a new truck to increase annually by $9%$ .
a Calculate the book value of the delivery truck in seven years' time.(2)
Show the memo (2 ticks)Memo
1. ✓
  Substitution $P = 296000$ ; $i = 0, 18$ ; $n = 7$
  $A = P (1 - i)^{n} = 296000 (1 - 0, 18)^{7}$
  1 mark · Calculate depreciation
2. ✓
  Answer $A = R 73788, 50$
  1 mark · Calculate depreciation

Compound Interest, Growth and Decay Grade 11 videos

Short lessons from South African teachers first. Videos load only when you tap play, to save your data.

Financial Maths Grade 10 | Simple Interest IntroductionKevinmathscience

Financial Maths Grade 10 | Compound Interest | IntroductionKevinmathscience

Financial maths grade 11 | DepreciationKevinmathscience

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