IMO Practice Test — Lines and Angles
6 Questions • 12 min • Olympiad level
12:00
Question 1 of 6
hard
Two equal angles together make a right angle. Each angle is…
45°
90°
30°
60°
Explanation: 90 ÷ 2 = 45°.
Question 2 of 6
medium
Two right angles together make…
a straight angle (180°)
a right angle
an acute angle
a full turn
Explanation: 90° + 90° = 180°.
Question 3 of 6
hard
How many 45° angles fit in a straight angle?
4
2
3
6
Explanation: 180 ÷ 45 = 4.
Question 4 of 6
hard
The opposite sides of a rectangle are…
parallel
perpendicular
curved
unequal
Explanation: Opposite sides of a rectangle are parallel.
Question 5 of 6
hard
The hands of a clock at 6 o'clock form a…
straight angle
right angle
acute angle
full turn
Explanation: At 6:00 the hands point opposite ways → 180°.
Question 6 of 6
medium
Perpendicular lines always form an angle of…
90°
45°
180°
60°
Explanation: Perpendicular lines meet at 90°.