Money Calculations (Cambridge (CIE) IGCSE Maths)

Money Calculations

What currencies can be used?

• Many different currencies are used

• The most commonly used currencies are

  • US Dollars ($ or USD)

  • Great British Pounds (£ or GBP)

  • Euros (€ or Euros)

  • It is possible to see other currencies used, with or without their symbols

What might I be asked to do in money calculations?

• Read exam questions carefully to identify key words

  • Total or sum will mean to add up

  • Difference or increase/decrease in costs will involve subtracting

  • Changing from one currency to another (exchange rates) will involve multiplying or dividing

• Some questions may involve a combination of these

  • E.g., Working out the total cost of an energy bill 

• Questions that involve money may also involve other topics in the course

  • E.g., Fractions, percentages, simple and compound interest etc.

How should I round values in a money calculation?

• Many currencies will be rounded to two decimal places

  • Dollars, pounds and euro should all be used to two decimal places

  • Always write down both decimal places, even if the second is zero

    • This is particularly important when using a calculator

    • 1.4 dollars on a calculator should be written as $1.40

• For a question involving large numbers such as the cost of a car

  • Rounding to the nearest dollar, 10 dollars or 100 dollars may be more appropriate

    • Use the information in the question to make a judgement

• Some currencies have large numbers due to exchange rates

  • These are usually rounded to the nearest whole number

  • E.g.,  $10 is 816.38 rupees making $100 the same as 8163.80 rupees

    • Rounding the exchange rate to $100 is 8160 rupees would be appropriate

What should I do when money calculations involve more than two decimal places?

• In some contexts money facts may be given to more than two decimal places

  • E.g. One litre of petrol in the UK costs an average price of £1.579

• Use all of the decimal places given in your working

  • Round (to two decimal places or whatever is appropriate) for your final answer only