Averages: Mean
Sum of values divided by their count.
Key idea
Sum of values divided by their count.
In depth
The mean is the sum of values divided by their count. It is the value each item would have if the total were shared out equally, so it balances the data like a seesaw.
Worked example
Scores 6, 8, 9, 5, 7: sum 35, divided by 5 gives a mean of 7.
Formula
Real-world uses
- Calculating average test scores, average speed over a journey and average monthly spending
Common mistake
Forgetting that outliers pull the mean strongly. One huge value distorts it.
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 Averages: Mean?
Sum of values divided by their count. It is a topic at the intermediate level in Arithmetic & Number Sense.
What is the formula for Averages: Mean?
The key formula is x̄ = Σx / n.
Where is Averages: Mean used in real life?
Real-world examples: Calculating average test scores, average speed over a journey and average monthly spending.
What should I learn before Averages: Mean?
Make sure you are comfortable with Money Arithmetic, the previous topic in Arithmetic & Number Sense.
What is a common mistake with Averages: Mean?
Forgetting that outliers pull the mean strongly. One huge value distorts it.
How can I practise Averages: Mean?
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 Averages: Mean?
Move on to Averages: Median and Mode next.
Related intermediate topics in Arithmetic & Number Sense
- Long Multiplication – Multiply by each digit of the multiplier, shift by place value, then add partial products.
- Long Division – Divide, multiply, subtract and bring down repeatedly to get the quotient.
- Factors and Multiples – Factors divide a number exactly; multiples are its products with whole numbers.
- Divisibility Rules – Quick tests: by 2 last digit even, by 3 digit-sum divisible by 3, by 5 ends 0/5, by 9 digit-sum divisible by 9.
- Prime Numbers – A prime has exactly two positive divisors: 1 and itself.
- Composite Numbers – Numbers greater than 1 with more than two factors.