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Classify and measure angles · Grade 4 · E1.3

Name: ______________________

Date: ______________________

1
Look at angle YDF below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
2
Look at angle ZQB below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
3
Look at angle RCQ 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 110°. What is the other angle, in degrees?
On level
708011060
5
Two angles are complementary, so together they measure 90°. One angle is 10°. What is the other angle, in degrees?
On level
170908010
6
Two angles are supplementary, so together they measure 180°. One angle is 130°. What is the other angle, in degrees?
On level
501304060
7
Three angles meet at a point and together make a full turn (360°). Two of them measure 100° and 90°. 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 40° 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 40° and 100°. What is the third angle, in degrees?
Challenge
Answer:

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Worksheet code: eyJzIjoic3BhdGlhbC1hbmdsZXMtY2xhc3NpZnkiLCJkIjpbMTMzNjY2MjI3MSwxNTIyODYxMDQyLDEyNTYyMzcyNDYsMTk0MzgzNjg3MSwxMTYzOTQ0OTUyLDIwNDYzMzgyMDUsNDg4MzExNjE4LDY5MzE0MTY1OSw0MzY4NTk3NDBdLCJ2IjoxfQ.90fbc7eaee85

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Answer key · Classify and measure angles

1.
30 — Read the angle on the protractor: it measures 30°.
2.
175 — Read the angle on the protractor: it measures 175°.
3.
55 — Read the angle on the protractor: it measures 55°.
4.
70 — Supplementary angles add to 180°, so the missing angle = 180 − 110 = 70.
5.
80 — Complementary angles add to 90°, so the missing angle = 90 − 10 = 80.
6.
50 — Supplementary angles add to 180°, so the missing angle = 180 − 130 = 50.
7.
170 — Angles around a point add to 360°, so the missing angle = 360 − 100 − 90 = 170.
8.
220 — Angles around a point add to 360°, so the missing angle = 360 − 40 − 100 = 220.
9.
220 — Angles around a point add to 360°, so the missing angle = 360 − 40 − 100 = 220.