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Classify and measure angles · Grade 4 · E1.3

Name: ______________________

Date: ______________________

1
Look at angle BDX below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
2
Look at angle ACE below. How many degrees does it measure? Write the number of degrees.
Warm-up
Answer:
3
Look at angle PQY 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 50°. What is the other angle, in degrees?
On level
4013050
5
Two angles are complementary, so together they measure 90°. One angle is 60°. What is the other angle, in degrees?
On level
304012060
6
Two angles are complementary, so together they measure 90°. One angle is 20°. What is the other angle, in degrees?
On level
160807020
7
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:
8
Three angles meet at a point and together make a full turn (360°). Two of them measure 80° and 50°. 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 100°. What is the third angle, in degrees?
Challenge
Answer:

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Worksheet code: eyJzIjoic3BhdGlhbC1hbmdsZXMtY2xhc3NpZnkiLCJkIjpbMTczOTg2MjI3OSwyMTQ3MTczOTc4LDg3Mzc0NTQ5NiwxOTM1MzIxOTY4LDcwMjQ3Mzk0OCw2NTQzNDUyMTAsNTczODc1MDMzLDU5NTg1MTM0MSw3MTE4NjM4OTVdLCJ2IjoxfQ.63c03fda8ece

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Answer key · Classify and measure angles

1.
30 — Read the angle on the protractor: it measures 30°.
2.
45 — Read the angle on the protractor: it measures 45°.
3.
85 — Read the angle on the protractor: it measures 85°.
4.
40 — Complementary angles add to 90°, so the missing angle = 90 − 50 = 40.
5.
30 — Complementary angles add to 90°, so the missing angle = 90 − 60 = 30.
6.
70 — Complementary angles add to 90°, so the missing angle = 90 − 20 = 70.
7.
230 — Angles around a point add to 360°, so the missing angle = 360 − 50 − 80 = 230.
8.
230 — Angles around a point add to 360°, so the missing angle = 360 − 80 − 50 = 230.
9.
160 — Angles around a point add to 360°, so the missing angle = 360 − 100 − 100 = 160.