MathsMonkey
Grade 12Mathematics
2026
Grade 12 Maths - Finance: Compound Interest & Annuities
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Instructions: State the formula before substituting. Identify each variable clearly. Round final answers to 2 decimal places.

Key formulas:

A=P(1+i)n(compound growth)A = P(1 + i)^n \quad \text{(compound growth)}

F=x[(1+i)n−1i](future value annuity)F = x\left[\frac{(1+i)^n - 1}{i}\right] \quad \text{(future value annuity)}

P=x[1−(1+i)−ni](present value annuity)P = x\left[\frac{1 - (1+i)^{-n}}{i}\right] \quad \text{(present value annuity)}

Section A: Compound Interest (6 marks)

  1. R 25 000 is invested at 8.5% p.a. compounded monthly for 6 years. Calculate the final value. (3)

  2. How long (in years) will it take R 10 000 to grow to R 18 000 at 9% p.a. compounded quarterly? (3)

Section B: Future Value Annuity (6 marks)

Thandi deposits R 1 500 at the end of each month into a savings account earning 7.2% p.a. compounded monthly.

  1. How much will she have after 5 years? (3)

  2. How much of this is interest? (1)

  3. If she needs R 120 000 after 5 years, calculate the required monthly deposit. (2)

Section C: Present Value / Loan (8 marks)

  1. Sipho takes out a home loan of R 850 000 at 11.5% p.a. compounded monthly, to be repaid over 20 years. Calculate the monthly instalment. (4)

  2. After 5 years of payments, calculate the outstanding balance on Sipho’s loan. (4)

Total: 20 marks