Angles Test Helper

4th Grade Unit 5 - English Translation with Hints

Key Vocabulary (Spanish → English)

ángulo → angle
grado(s) → degree(s)
ángulo recto → right angle (90°)
ángulo agudo → acute angle (<90°)
ángulo obtuso → obtuse angle (>90°)
círculo → circle
fracción → fraction
medida → measure
transportador → protractor
dibuja → draw
etiqueta → label
porción → portion/slice
reloj → clock
manecillas → clock hands
justifica → justify/explain

Key Concepts to Remember

A full circle = 360° — This is the most important number for this test!
Acute angle: Less than 90° (sharp, small)
Right angle: Exactly 90° (makes an "L" shape)
Obtuse angle: More than 90° but less than 180° (wide, open)
To find one slice: 360° ÷ number of equal pieces
Question 1 6 Points
Use the image to answer the following questions.

Look at the geometric figure shown (rectangle with diagonal lines creating triangles inside).

Part A: Label the RIGHT angles in the image with the letter "R".

Part B: Label the ACUTE angles in the image with the letter "A".

Part C: Label the OBTUSE angles in the image with the letter "O".

Step-by-Step Approach:

  1. Find Right Angles (R): Look for corners that make a perfect "L" shape (90°). The corners of the rectangle are right angles!
  2. Find Acute Angles (A): Look for angles that are smaller/sharper than a right angle. The pointy angles where the diagonal lines meet are acute.
  3. Find Obtuse Angles (O): Look for angles that are wider/more open than a right angle. Some angles where diagonals cross may be obtuse.
Tip: Use the corner of a piece of paper as a reference for a right angle. If the angle is smaller, it's acute. If it's bigger, it's obtuse.
Question 2 6 Points
Draw an example of a right angle, an acute angle, and an obtuse angle.

Label each angle as right, acute, or obtuse.

What to Draw:

📐
Right Angle
Exactly 90°

Draw an "L" shape

📏
Acute Angle
Less than 90°

Draw a sharp, narrow angle

📖
Obtuse Angle
90° to 180°

Draw a wide, open angle

Tip: Don't forget to write the label next to each angle you draw!
Question 3 1 Point
Which figure has 2 acute angles and 1 right angle?

Look at the four shapes shown: A (parallelogram), B (irregular quadrilateral), C (trapezoid), D (rectangle/square).

Step-by-Step Approach:

  1. Count the angles in each shape
  2. Identify which angles are acute (less than 90°)
  3. Identify which angle is exactly 90° (right angle)
  4. Find the shape with exactly 2 acute + 1 right angle
Tip: A right triangle has exactly 1 right angle and 2 acute angles! Look for a triangle shape or a shape that contains these angles.
Question 4 2 Points
Draw an obtuse angle. Measure it and write how many degrees it measures.

Write your answer on the line labeled "Grados:" (Degrees:)

Step-by-Step Approach:

  1. Draw: Make an angle that is wider/more open than a right angle (bigger than 90°)
  2. Measure: Use the protractor shown in the image
    • Place the center of the protractor at the vertex (corner) of your angle
    • Line up one ray with 0°
    • Read where the other ray crosses the protractor
  3. Write: Your answer should be a number between 91° and 179°
Tip: An obtuse angle must be MORE than 90° but LESS than 180°. Examples: 100°, 120°, 150°
Question 5 1 Point
Angle POQ is shown below. What would be the degree measure of the rest of the circle?

The angle POQ shown measures 85°.

Step-by-Step Approach:

  1. Remember: A full circle = 360°
  2. The angle POQ takes up 85° of the circle
  3. Subtract to find the rest: 360° - 85° = ?
360° - 85° = 275°
Answer: The rest of the circle is 275°
Question 6 1 Point
What fraction of a circle is 1 degree?

A. 1/360

B. 1/100

C. 1/90

D. 1/1

Think About It:

  1. A full circle has 360 degrees total
  2. If the whole circle is 360°, then 1° is ONE part out of 360 parts
  3. As a fraction: 1 out of 360 = 1/360
1 degree = 1/360 of a circle
Answer: A. 1/360
Question 7 2 Points
Use the protractor to answer the following question.

The protractor shows points F, G, and H. Point G is at the center.

Question: What is the measure of angle FGH?

Question: What type of angle is it?

How to Read a Protractor:

  1. Find the vertex: G is at the center of the protractor
  2. Find where F is: Look at which number F lines up with on the protractor
  3. Find where H is: Look at which number H lines up with
  4. Calculate: The angle measure is the difference between these two numbers (or read directly if one ray is at 0°)
  5. Classify:
    • If less than 90° → Acute (agudo)
    • If exactly 90° → Right (recto)
    • If more than 90° → Obtuse (obtuso)
Tip: Look carefully at the protractor image in your test. Read where each point is located and subtract to find the angle.
Question 8 5 Points
Samira's mom bought a circular cake as shown.

The cake will be divided equally among 8 people. Divide the circle into 8 equal portions.

Part A: What will be the angle measure of ONE portion of cake? Justify your answer.

Part B: What will be the angle measure of 3 CONSECUTIVE portions of cake? Justify your answer.

Part A - One Slice:

  1. A full circle = 360°
  2. Divide equally into 8 portions
  3. Each portion = 360° ÷ 8
360° ÷ 8 = 45°

Answer Part A: Each portion is 45°

Justification: "A circle has 360 degrees. 360 ÷ 8 = 45, so each portion is 45 degrees."

Part B - Three Slices:

  1. We know one slice = 45°
  2. Three consecutive slices = 3 × 45°
3 × 45° = 135°

Answer Part B: Three portions = 135°

Justification: "Each portion is 45 degrees. 3 × 45 = 135, so three portions is 135 degrees."

Question 9 2 Points
Use the clock to answer the following questions.

The clock shows 3:00 (hour hand on 3, minute hand on 12).

Part A: What angle measure in degrees do the clock hands represent?

Part B: What fraction of the circle do the clock hands represent?

Part A - Degrees:

  1. A clock is a circle with 12 hours
  2. Full circle = 360°
  3. Each hour = 360° ÷ 12 = 30°
  4. From 12 to 3 = 3 hours
  5. Angle = 3 × 30° = 90°
3 hours × 30° per hour = 90°

Answer Part A: The clock hands form a 90° angle (right angle)

Part B - Fraction:

  1. The angle is 90° out of 360°
  2. As a fraction: 90/360
  3. Simplify: 90/360 = 1/4
90° ÷ 360° = 1/4

Answer Part B: The clock hands represent 1/4 (one quarter) of the circle

Another way to think about it: From 12 to 3 is 3 hours out of 12 total hours. 3/12 = 1/4
Question 10 2 Points
A circular pizza is cut into 5 equal portions as shown.

What equations can be used to determine the angle measure of one pizza slice? Select TWO answer choices.

A. 5 ÷ 360 = m

B. 180 ÷ 5 = m

C. 360 ÷ 5 = m

D. m × 5 = 180

E. 5 × m = 360

F. 360 × 5 = m

Think About It:

  1. We want to find the angle (m) of ONE slice
  2. Full circle = 360° (not 180°!)
  3. There are 5 equal slices
  4. So: 360° ÷ 5 = one slice

Check Each Option:

  • A. 5 ÷ 360 = m ❌ This is backwards (would give a tiny number)
  • B. 180 ÷ 5 = m ❌ Uses 180 instead of 360
  • C. 360 ÷ 5 = m ✅ Correct! This gives us 72°
  • D. m × 5 = 180 ❌ Uses 180 instead of 360
  • E. 5 × m = 360 ✅ Correct! Same as C, just rearranged (m = 72°)
  • F. 360 × 5 = m ❌ This multiplies instead of divides (would give 1800)
360 ÷ 5 = 72° per slice
Answers: C and E
Both equations give you m = 72°

Good luck on your test!

Remember: A full circle is always 360°