Secondary 3 G2 Mathematics Tutor Bukit Timah | Box Plots, Quartiles and Interquartile Range. Did you know? Two classes can have the same median but different spreads.
This guide helps Secondary 3 G2 Mathematics students in Bukit Timah understand box plots, quartiles and interquartile range through concise explanations, worked examples and checks. A box plot summarises minimum, lower quartile, median, upper quartile and maximum. The box extends from Q1 to Q3.
Quick answer: Box Plots, Quartiles and Interquartile Range
Two classes can have the same median but different spreads. A box plot summarises minimum, lower quartile, median, upper quartile and maximum. The box extends from Q1 to Q3.
Worked example: the first important method
For ordered data 2, 4, 5, 7, 9, 10, 12, the median is 7; using the median-of-halves convention, Q1=4 and Q3=10.
Worked example: change the conditions
The interquartile range is Q3−Q1=6. The full range is 12−2=10. These are different measures of spread.
How to check the result
Compare medians to discuss centres and box widths to compare the middle halves of distributions. A wider box indicates a larger IQR. Quartile conventions may vary for particular datasets; follow the stated question method and school guidance. This K210 content is underlined for Paper 2 Section B.
A practical revision plan
First, identify the given information and define the unknown. Next, solve a worked example with every reason or algebraic step shown. Then change the numbers or diagram and attempt the question independently. Finally, revisit it after several days. Quartile conventions may vary for particular datasets; follow the stated question method and school guidance. This K210 content is underlined for Paper 2 Section B.
Frequently asked questions
What should I check first? Read the question, identify the given quantities and the required result. Why can the answer look plausible but be wrong? A misplaced sign, incorrect diagram correspondence or wrong unit can invalidate an otherwise neat calculation. How can parents help? Ask the learner to explain the first step, not simply quote a formula.
Official syllabus and learning support
Use the 2027 SEC G2 Mathematics K210 syllabus for the precise assessment scope. The unchanged eduKateSG small-group Mathematics reference describes the existing teaching model near Sixth Avenue. Confirm actual Secondary 3 G2 class availability, tutor, timetable and fees directly.
Continue learning
For related Mathematics work, see the right-triangle checking guide, the probability rules guide, and the circle chords and tangents guide.
Ask the student to complete a changed question without prompts and explain why the method works. Quartile conventions may vary for particular datasets; follow the stated question method and school guidance. This K210 content is underlined for Paper 2 Section B.