Money Arithmetic
Adding, subtracting and making change with currency.
Key idea
Adding, subtracting and making change with currency.
In depth
Money uses decimals with two places for cents. Calculate totals, change, and unit prices using decimal arithmetic. Estimate first to check reasonableness.
Worked example
3 items at 4.25 pay with a 20 note: 3 × 4.25 = 12.75, change = 20 − 12.75 = 7.25.
Real-world uses
- Making change at a till
- Budgeting weekly spending
- Comparing wages and bills in different currencies
Common mistake
Rounding too early and accumulating cent errors.
How to learn this
- Read the key idea and say it in your own words.
- Work through the worked example, then try a similar problem.
- Use the interactive lesson’s visual and mini-quiz to check the pattern.
Frequently asked questions
What is Money Arithmetic?
Adding, subtracting and making change with currency. It is a topic at the beginner level in Arithmetic & Number Sense.
Where is Money Arithmetic used in real life?
Real-world examples: Making change at a till; Budgeting weekly spending; Comparing wages and bills in different currencies.
What should I learn before Money Arithmetic?
Make sure you are comfortable with Time and Clocks, the previous topic in Arithmetic & Number Sense.
What is a common mistake with Money Arithmetic?
Rounding too early and accumulating cent errors.
How can I practise Money Arithmetic?
Open the interactive lesson, play with the visual, then answer the three-question mini-quiz. Getting two right marks the topic complete.
What comes after Money Arithmetic?
Move on to Averages: Mean next.
Related beginner topics in Arithmetic & Number Sense
- Counting & Cardinality – Assigning one number word to each object to find how many there are.
- Place Value – The value of a digit depends on its position: ones, tens, hundreds and so on.
- Number Line – A line where numbers are placed in order at equal spacing to compare and add them.
- Comparing Numbers – Use <, > and = to say which number is smaller, larger or equal.
- Ordering Numbers – Arranging numbers from least to greatest or the reverse.
- Even and Odd Numbers – Even numbers divide by 2 with no remainder; odd numbers leave remainder 1.