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Classify and measure angles · Grade 4 · E1.3

Name: ______________________

Date: ______________________

1
Look at angle QBF below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
2
Look at angle CXY below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
3
Look at angle BZP below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
4
Two angles are complementary, so together they measure 90°. One angle is 70°. What is the other angle, in degrees?
On level
302011070
5
Two angles are complementary, so together they measure 90°. One angle is 30°. What is the other angle, in degrees?
On level
701503060
6
Two angles are complementary, so together they measure 90°. One angle is 40°. What is the other angle, in degrees?
On level
140506040
7
Three angles meet at a point and together make a full turn (360°). Two of them measure 50° and 60°. 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 50° and 80°. 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 80°. What is the third angle, in degrees?
Challenge
Answer:

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Worksheet code: eyJzIjoic3BhdGlhbC1hbmdsZXMtY2xhc3NpZnkiLCJkIjpbMTU2OTY3MDMxOSw2NjU5NzA5NCw2MTcxMjQzNDEsMTk4NTQ0OTM3NywxMDczMzcyMDY4LDY5NzkyOTE0Myw1MTMxNDUzNjEsNTE1Mjk3ODc1LDEwMzEwMjgzNDZdLCJ2IjoxfQ.f54d71e908f4

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Answer key · Classify and measure angles

1.
95 — Read the angle on the protractor: it measures 95°.
2.
125 — Read the angle on the protractor: it measures 125°.
3.
105 — Read the angle on the protractor: it measures 105°.
4.
20 — Complementary angles add to 90°, so the missing angle = 90 − 70 = 20.
5.
60 — Complementary angles add to 90°, so the missing angle = 90 − 30 = 60.
6.
50 — Complementary angles add to 90°, so the missing angle = 90 − 40 = 50.
7.
250 — Angles around a point add to 360°, so the missing angle = 360 − 50 − 60 = 250.
8.
230 — Angles around a point add to 360°, so the missing angle = 360 − 50 − 80 = 230.
9.
240 — Angles around a point add to 360°, so the missing angle = 360 − 40 − 80 = 240.