Chapter 9: Mixed Number and Statistics Review
Mixed Number and Statistics Review
Switch topics intelligently and choose the method that earns marks in unfamiliar questions.
AI teacher
Start the short explanation, then use the visual model and practice before returning to the workbook.
Voice: Browser voice
Workbook pages
Junior Maths Book 1 pages 152-160
Blend number, ratio, data and probability skills in cumulative exam-style review sets.
AI explanation
The AI teacher treats mixed review as exam rehearsal. Students learn to identify topic signals, plan methods, show working, interpret answers and check reasonableness.
- 1Mixed questions test recognition as much as calculation.
- 2First identify the topic signal: number, ratio, data, statistics or probability.
- 3Choose a method before calculating.
- 4Write enough working for another person to follow.
- 5Check the answer against the question context.
Animated teaching
See the method
Question cards sort into number, ratio, statistics and probability, then a checklist shows plan, solve, interpret and check.
Identify
topic signal
Plan
method
Solve
show working
Check
reasonable answer
Why this method works
- Topic recognition reduces panic in unfamiliar questions.
- Clear working protects method marks.
- Checking reasonableness catches arithmetic slips before final answers are written.
Common mistakes
- Starting calculations before understanding the question.
- Using a formula from the wrong topic.
- Writing a number without units or interpretation.
- Not revisiting a result that is clearly unreasonable.
Multiple methods
- A problem can often be represented as a table, bar model, equation or graph.
- Statistics questions can be checked with totals and frequencies.
- Number questions can be checked with estimation.
Worked examples
Mixed statistics reasoning
A grouped table has modal class 3-5. Explain what this tells us.
Method: Interpret the class with highest frequency.
- 1.The modal class is the interval with the greatest frequency.
- 2.It does not tell the exact most common value.
- 3.It tells the most common interval.
Answer: Most values are in the 3-5 class interval.
Mixed number checking
Estimate 397 x 51 divided by 0.201 using 1 significant figure.
Method: Round each number to 1 significant figure.
- 1.397 rounds to 400.
- 2.51 rounds to 50.
- 3.0.201 rounds to 0.2.
- 4.400 x 50 divided by 0.2 = 20 000 divided by 0.2.
Answer: 100 000
Interactive practice
Try before you look
Question 1
A question says 'modal class'. Which topic is it using?
Question 2
A final answer is 3.6 people. What should you do?
Question 3
Which action helps earn method marks?
Review prompt
Describe your mixed-question routine in four words: identify, plan, solve, check.
Write a two-sentence answer in your notebook before marking the workbook section complete.
Challenge question
A student estimates a standard-form calculation and gets 0.00008 for a result that should be about 80 000. Give two likely checking signals they missed.
Hint: Think about powers of 10 and whether the size is reasonable.