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Excel in math and science
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Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, interactive explorations.
Used and loved by over 6 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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Discrete Mathematics
Discrete Mathematics Warmups
Intro
Concept Quizzes
Rearranging Blocks
Counting Triangles
Quadruplets Ordering
Arrangement Puzzles
Recursion
Walking in a Rectangular Grid
Challenge Quizzes
Level 1
Level 2
Level 3
Level 4
Level 5
Counting Triangles Warmup
How many triangles can you find in this figure?
6
5
7
4
Submit
How many triangles can you find in this figure?
8
6
3
12
Submit
How many triangles can you find in this picture?
12
13
18
9
Submit
How many triangles can you find in this figure?
16
10
14
20
Submit
How many triangles can you find in this figure?
4
3
5
6
Submit
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