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Classify and measure angles · Grade 4 · E1.3

Name: ______________________

Date: ______________________

1
Look at angle XEQ below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
2
Look at angle DAQ below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
3
Look at angle CQE below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
4
Two angles are supplementary, so together they measure 180°. One angle is 60°. What is the other angle, in degrees?
On level
Answer:
5
Two angles are supplementary, so together they measure 180°. One angle is 60°. What is the other angle, in degrees?
On level
Answer:
6
Two angles are supplementary, so together they measure 180°. One angle is 110°. What is the other angle, in degrees?
On level
Answer:
7
Three angles meet at a point and together make a full turn (360°). Two of them measure 80° and 80°. What is the third angle, in degrees?
Challenge
Answer:
8
Three angles meet at a point and together make a full turn (360°). Two of them measure 70° and 100°. What is the third angle, in degrees?
Challenge
Answer:
9
Three angles meet at a point and together make a full turn (360°). Two of them measure 100° and 40°. What is the third angle, in degrees?
Challenge
Answer:

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Worksheet code: eyJzIjoic3BhdGlhbC1hbmdsZXMtY2xhc3NpZnkiLCJkIjpbMTEzNTQwOTM4MSw1MjI3NTAyMjUsMjkwMzE2Njk5LDgzNTc3NzY2MywxMTU4OTQ0MCwxODc5NTkxODA5LDY2MDEyMzU2NywxODc0NDg1ODcyLDEyODIzMDU1NDRdLCJ2IjoxfQ.fff56e44c817

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Answer key · Classify and measure angles

1.
45 — Read the angle on the protractor: it measures 45°.
2.
80 — Read the angle on the protractor: it measures 80°.
3.
90 — Read the angle on the protractor: it measures 90°.
4.
120 — Supplementary angles add to 180°, so the missing angle = 180 − 60 = 120.
5.
120 — Supplementary angles add to 180°, so the missing angle = 180 − 60 = 120.
6.
70 — Supplementary angles add to 180°, so the missing angle = 180 − 110 = 70.
7.
200 — Angles around a point add to 360°, so the missing angle = 360 − 80 − 80 = 200.
8.
190 — Angles around a point add to 360°, so the missing angle = 360 − 70 − 100 = 190.
9.
220 — Angles around a point add to 360°, so the missing angle = 360 − 100 − 40 = 220.