Primary 6 · Chapter 9
Find areas of triangles, folded paper and overlapping shapes. Follow the introduction, then try the questions.
Self-paced lessons · Modelled on top school exam questions · No sign-up for the samples
The Area chapter
Watch · The introduction
Start with a triangle inside a rectangle, then use equal heights, folds and overlaps.
Try · Modelled on top school exam questions
Try each question yourself first, then check your answer or compare it with the solution. These questions are written by Mathweave, not copied from school papers. No sign-up is needed.
Question 1 of 3
Use the rectangle's area and the triangle's position to find the missing area.
KLMN is a rectangle with an area of 156 cm². T is a point on the side LM. Find the area of triangle KNT.
Ans: 78 cm²
Question 2 of 3
Use the shared height and the base lengths to compare the triangle areas.
In the figure, P, Q and R lie on a straight line and S is a point above the line. PQ is 3 units long and QR is 5 units long. The area of triangle QRS is 45 cm². Find the area of triangle PQS.
Ans: 27 cm²
Question 3 of 3
Use the two identical rectangles and their crossed arrangement to find the total covered area.
Two identical rectangles, each 15 cm by 8 cm, are laid across each other so that the part where they cross is a square of side 8 cm. Find the area of the figure the two rectangles cover.
Ans: 176 cm²
Follow a lesson link beside a question, or browse the chapter below.
The chapter · Four question types
A linked row opens a published lesson with its own film. Explore the explanation and available practice on that page.
Mixed practice, where the types return unannounced and unlabelled, is a chapter-level activity. It has no lesson page of its own.
The order · Two groups
Composite figures, and the pieces they are built from
9.1 and 9.2
Paper folded over, and a base marked in units
9.3 and 9.4
The number tells you where a question type sits in this chapter, not what your child needs to learn first. A child who has already met a type in school can practise it without working through the ones above it.
The papers · Modelled against top school papers
Paper 1 has 30 questions for 50 marks: 18 multiple-choice questions and 12 short-answer questions. Paper 2 has 15 questions for 50 marks: 5 short-answer questions and 10 structured or long-answer questions.
A Paper 1 item is usually one shape and one rule, often answered by picking from four options. The three-mark and four-mark items appear in Paper 2, and they are almost always a figure built from squares, rectangles and triangles with a part shaded, two identical shapes laid over one another, or a sheet folded so that some of it lies on top of the rest. The harder items often combine area with fractions or ratio. Practice questions are not labelled by type, so children must choose the methods they need.
Base and height of a triangle, the area of a triangle, and composite figures made up of rectangles, squares and triangles are Primary 5 outcomes in the current MOE syllabus, and the PSLE sets them again. Some appear in higher-mark Paper 2 questions, so this chapter teaches them in the form used in Primary 6.
Everything here is modelled against top school papers. Those papers are never reproduced, and every question on this site is original.
Written working · Clear methods, line by line
These examples show Mathweave's clear, consistent layout for each method. The layout is informed by the answer keys we reviewed.
Parents · Asked and answered
The question types follow the latest MOE Primary Mathematics syllabus. The syllabus defines what is taught; the papers we model against show how it is examined.
The papers set base and height of a triangle, and figures built from squares, rectangles and triangles, right through Primary 6, and they set them at three and four marks. This chapter teaches that material in the form used in Primary 6.
We write the questions ourselves rather than copy them from papers. Each chapter is modelled on the types of question that top school papers set. A question may look like one your child has met before because it is the same type.
Practice uses different numbers for each question type, points out the common mistake when your child makes it and records which types your child can complete independently.