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Year 8 Maths — Simple interest

Work out simple interest and the total amount, and find the rate or the time when the interest is known.

Name: ________________________

  1. 1.In a simple interest question, what does the rate tell you?

    • a) The number of years the money is kept for
    • b) The amount borrowed at the start
    • c) The total interest over the whole time
    • d) The interest earned on every 100 of the principal in one year

  2. 2.The principal and the rate stay the same, but the money is left for twice as long. What happens to the simple interest?

    • a) It stays the same
    • b) It doubles
    • c) It is multiplied by itself
    • d) It halves

  3. 3.Find the simple interest on £5000 at 8% per year for 2 years. Give just the number.

  4. 4.The simple interest on £2500 for 4 years is £500. What is the rate per cent per year? Give just the number.

  5. 5.Find the simple interest on £1200 at 10% per year for 1 year. Give just the number.

  6. 6.The simple interest on £800 at 5% per year is £200. For how many years was the money invested?

  7. 7.Each of these is left for 2 years. Sort them by whether the simple interest comes to less or more than £500.

    Groups: Less than £500 · More than £500

    • £2000 at 10% per year
    • £3000 at 5% per year
    • £5000 at 8% per year
    • £1000 at 20% per year
    • £5000 at 6% per year
    • £4000 at 8% per year

  8. 8.Find the simple interest on £600 at 12% per year for 5 years. Give just the number.

Answer key — Year 8 Maths — Simple interest

  1. 1. d) The interest earned on every 100 of the principal in one year
  2. 2. b) It doubles
  3. 3. 800
  4. 4. 5
  5. 5. 120
  6. 6. 5
  7. 7. £2000 at 10% per year → Less than £500; £5000 at 6% per year → More than £500; £1000 at 20% per year → Less than £500; £4000 at 8% per year → More than £500; £3000 at 5% per year → Less than £500; £5000 at 8% per year → More than £500
  8. 8. 360