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Free Grade 3 Introducing Angle Bisector Essentials Quizzes

Free Grade 3 quizzes for Introducing Angle Bisector Essentials: 12 real questions with a full answer key and worked solutions. Angles on a straight line add to 180°, around a point to 360°, and inside a triangle to 180°. A polygon with n sides has interior angles adding to (n − 2) × 180°.

Price

Free

Difficulty

Higher

Estimated time

25 min

Total marks

24

Learning objectives

Every objective is checkable, and each one maps to an activity and an assessment.

  • UnderstandExplain introducing angle bisector essentials

    Explain introducing angle bisector essentials accurately in a familiar context.

    Assessed by: Exit ticket of four short items

  • ApplyCalculate introducing angle bisector essentials

    Calculate introducing angle bisector essentials accurately in a familiar context.

    Assessed by: Exit ticket of four short items

  • AnalyseCompare introducing angle bisector essentials

    Compare introducing angle bisector essentials accurately in a familiar context.

    Assessed by: Exit ticket of four short items

  • EvaluateJustify introducing angle bisector essentials

    Justify introducing angle bisector essentials accurately in a familiar context.

    Assessed by: Exit ticket of four short items

Prerequisites

Close these gaps first — each has its own free lesson, worksheet and quiz.

How Introducing Angle Bisector Essentials works

Angles on a straight line add to 180°, around a point to 360°, and inside a triangle to 180°. A polygon with n sides has interior angles adding to (n − 2) × 180°.

Key wordsdegreeacuteobtusereflexinterior angle

12 practice questions

Easy to hard, 24 marks in total. Try them first, then open the answers.

  1. 1.Two angles on a straight line. One is 86°. Find the other.[1]
  2. 2.Two angles on a straight line. One is 87°. Find the other.[1]
  3. 3.Two angles on a straight line. One is 139°. Find the other.[1]
  4. 4.Two angles on a straight line. One is 30°. Find the other.[1]
  5. 5.A triangle has angles 40° and 43°. Find the third angle.[2]
  6. 6.A triangle has angles 77° and 68°. Find the third angle.[2]
  7. 7.A triangle has angles 72° and 46°. Find the third angle.[2]
  8. 8.A triangle has angles 80° and 57°. Find the third angle.[2]
  9. 9.Find the size of each interior angle of a regular 6-sided polygon.[3]
  10. 10.Find the size of each interior angle of a regular 5-sided polygon.[3]
  11. 11.Find the size of each interior angle of a regular 10-sided polygon.[3]
  12. 12.Find the size of each interior angle of a regular 9-sided polygon.[3]
Show answers and working
  1. 1. 94°

    Angles on a straight line add to 180°. 180 − 86 = 94°.

  2. 2. 93°

    Angles on a straight line add to 180°. 180 − 87 = 93°.

  3. 3. 41°

    Angles on a straight line add to 180°. 180 − 139 = 41°.

  4. 4. 150°

    Angles on a straight line add to 180°. 180 − 30 = 150°.

  5. 5. 97°

    Angles in a triangle add to 180°. 180 − 40 − 43 = 97°.

  6. 6. 35°

    Angles in a triangle add to 180°. 180 − 77 − 68 = 35°.

  7. 7. 62°

    Angles in a triangle add to 180°. 180 − 72 − 46 = 62°.

  8. 8. 43°

    Angles in a triangle add to 180°. 180 − 80 − 57 = 43°.

  9. 9. 120°

    Sum of interior angles = (6 − 2) × 180 = 720°. Each angle = 720 ÷ 6 = 120°.

  10. 10. 108°

    Sum of interior angles = (5 − 2) × 180 = 540°. Each angle = 540 ÷ 5 = 108°.

  11. 11. 144°

    Sum of interior angles = (10 − 2) × 180 = 1440°. Each angle = 1440 ÷ 10 = 144°.

  12. 12. 140°

    Sum of interior angles = (9 − 2) × 180 = 1260°. Each angle = 1260 ÷ 9 = 140°.

Worked examples

Easy example

Two angles on a straight line. One is 156°. Find the other.

  1. Angles on a straight line add to 180°.
  2. 180 − 156 = 24°.
  3. Answer: 24°
Medium example

A triangle has angles 20° and 93°. Find the third angle.

  1. Angles in a triangle add to 180°.
  2. 180 − 20 − 93 = 67°.
  3. Answer: 67°
Hard example

Find the size of each interior angle of a regular 7-sided polygon.

  1. Sum of interior angles = (7 − 2) × 180 = 900°.
  2. Each angle = 900 ÷ 7 = 128.57°.
  3. Answer: 128.57°

Interactive practice

Free, no account required — answer on screen or print it.

Common mistakes

What learners typically get wrong, and how to fix it.

  • Reads the wrong scale on a protractor.

    Correction: Start from the 0 on the arm you are measuring from.

  • Uses 360° for a triangle.

    Correction: Triangle = 180°, quadrilateral = 360°.

Teacher tips

  • · Estimate the angle type before measuring.

Parent tips

  • · Spot right angles around the house.

Real-life applications

  • · Ramps, clock hands, building and design.

Assessment objectives

How mastery is evidenced, and which standards it maps to.

FBISE FBI-276.1 — Mapped statement covering Introducing Angle Bisector Essentials.COMMON-CORE COM-728.2 — Mapped statement covering Introducing Angle Bisector Essentials.

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Frequently asked

Is this Grade 3 Introducing Angle Bisector Essentials quiz really free?
Yes. Every quizzes on FreeMathWorksheet is free to use, print and share — no account, no paywall and no watermark.
What should a learner already know before this?
Start with Perpendicular Bisector. Each one has its own free lesson, worksheet and quiz.
How is the quiz sequenced?
Recognition first, then understanding, application, reasoning and finally mastery — the same ladder used across every free resource on the platform.
What comes next after Introducing Angle Bisector Essentials?
Move on to Introducing Angle Bisector Techniques, Introducing Angle Bisector Word Problems, Introducing Angle Bisector Common Errors, Working with Angle Bisector, which build directly on this idea.

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