Complementary angles

Difficulty Standard · Set vp7dkb

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1
The two angles are complementary. One is 55°. What is the other, in degrees?
2
The two angles are complementary. One is 20°. What is the other, in degrees?
3
The two angles are complementary. One is 30°. What is the other, in degrees?
4
The two angles are complementary. One is 65°. What is the other, in degrees?
5
The two angles are complementary. One is 55°. What is the other, in degrees?
6
The two angles are complementary. One is 60°. What is the other, in degrees?
7
The two angles are complementary. One is 55°. What is the other, in degrees?
8
The two angles are complementary. One is 70°. What is the other, in degrees?
9
The two angles are complementary. One is 60°. What is the other, in degrees?
10
The two angles are complementary. One is 35°. What is the other, in degrees?
11
The two angles are complementary. One is 70°. What is the other, in degrees?
12
The two angles are complementary. One is 15°. What is the other, in degrees?
13
The two angles are complementary. One is 55°. What is the other, in degrees?
14
The two angles are complementary. One is 20°. What is the other, in degrees?
15
The two angles are complementary. One is 45°. What is the other, in degrees?
16
The two angles are complementary. One is 30°. What is the other, in degrees?
17
The two angles are complementary. One is 55°. What is the other, in degrees?
18
The two angles are complementary. One is 55°. What is the other, in degrees?
19
The two angles are complementary. One is 30°. What is the other, in degrees?
20
The two angles are complementary. One is 20°. What is the other, in degrees?

What is in this set

The numbers in this set run from 15 to 70.
A careful solution takes 1 written step on average.
The mistake this set invites most often, in 100% of the problems: complementary angles add to 90°, not 180°.
Answers are a whole number.

Drawing 240 problems from this page produced 12 different ones, 5% — so a sheet of 20 will come back to a problem you have seen — there are only so many sensible ones of this kind.

The same skill, harder or easier

We would put this in front of a grade 5 class. That is our judgement, not a standard, and it is printed here so you can disagree with it. Everything else we put in that year.