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Primary 6 · Mathematics · Angles

Angles questions for Primary 6 Maths

10 questions to work through online. Answer and you get the working straight away, then a score at the end. No sign-up, and you can retake it as often as you like.

  • Angles on a straight line
  • Angles at a point
  • Vertically opposite angles
  • Complementary angles
  • Naming angles
  • Interior angle of a regular polygon
  • Adjacent angles on a line
  • Exterior angle
  • Finding an unknown
  • Reflex angle
0 of 10 answered
Question 1 of 10Angles on a straight line
Two angles sit on a straight line. One of them is 127°. What is the other?
Question 2 of 10Angles at a point
Three angles meet at a point. Two of them are 95° and 140°. What is the third?
Question 3 of 10Vertically opposite angles
Two straight lines cross. One of the angles formed is 74°. What is the angle opposite it?
Question 4 of 10Complementary angles
Two angles are complementary. One of them is 38°. What is the other?
Question 5 of 10Naming angles
An angle of 180° is called a
Question 6 of 10Interior angle of a regular polygon
What is each interior angle of a regular pentagon?
Question 7 of 10Adjacent angles on a line
Three angles sit on a straight line. Two of them are 40° and 75°. What is the third?
Question 8 of 10Exterior angle
What is each exterior angle of a regular octagon?
Question 9 of 10Finding an unknown
Angle AOB and angle BOC sit on a straight line. Angle AOB is twice angle BOC. What is angle AOB?
Question 10 of 10Reflex angle
A reflex angle is 250°. What is the smaller angle that sits with it at the same point?
Answers and explanations for all 10 questions

Every answer with the reasoning behind it. Worth reading after you have tried the set — or on its own, if you are a parent marking it.

  1. Two angles sit on a straight line. One of them is 127°. What is the other?

    Answer: 53°

    Angles on a straight line add to 180°, so 180 − 127 = 53°.

  2. Three angles meet at a point. Two of them are 95° and 140°. What is the third?

    Answer: 125°

    Angles at a point add to 360°, so 360 − 95 − 140 = 125°.

  3. Two straight lines cross. One of the angles formed is 74°. What is the angle opposite it?

    Answer: 74°

    Vertically opposite angles are equal, so the opposite angle is also 74°.

  4. Two angles are complementary. One of them is 38°. What is the other?

    Answer: 52°

    Complementary angles add to 90°, so 90 − 38 = 52°.

  5. An angle of 180° is called a

    Answer: straight angle

    A straight angle is 180° — a half turn, a straight line.

  6. What is each interior angle of a regular pentagon?

    Answer: 108°

    Sum = (5 − 2) × 180° = 540°, and 540 ÷ 5 = 108°.

  7. Three angles sit on a straight line. Two of them are 40° and 75°. What is the third?

    Answer: 65°

    The three angles add to 180°, so 180 − 40 − 75 = 65°.

  8. What is each exterior angle of a regular octagon?

    Answer: 45°

    The exterior angles of any polygon add to 360°, so 360 ÷ 8 = 45°.

  9. Angle AOB and angle BOC sit on a straight line. Angle AOB is twice angle BOC. What is angle AOB?

    Answer: 120°

    Let BOC be 1 unit. Then AOB is 2 units and 3 units = 180°, so AOB is 120°.

  10. A reflex angle is 250°. What is the smaller angle that sits with it at the same point?

    Answer: 110°

    The two angles at a point add to 360°, so 360 − 250 = 110°.