The Proof! tabletop card game is the inspiration behind our free, online Math Puzzle Challenges. Each carefully constructed puzzle consists of a set of nine cards that hides a challenging equation. If you would like, you can create an account to save your progress. Or if you already have an account, you can log in.

1.
Find a Pair of 6's
2.
Find Any Pair Using Only Division
3.
Find Any Pair Greater Than 100
4.
Find Any Triplet Using At Least 6 Cards
5.
Find a Triplet of 7's Using At Least 7 Cards
6.
Find Any Pair of Fractions
7.
Find Any Triplet of Fractions
8.
Find Any Pair Less Than 0
9.
Find Any Pair Greater Than 50 Using Only Multiplication
10.
Find 9 Different Pairs Using Exactly 3 Cards Each
11.
Find 4 Different Triplets
12.
Find a Pair of 100's
13.
Find Any Pair Using All 9 Cards
14.
Find Any Quadruplet
15.
Find Any Triplet Less Than 0
16.
Find Any Pair Using Only Subtraction
17.
Find a Quadruplet of 1's
18.
Find Any Pair Using At Least 3 Square Roots
19.
Find Any Pair Using the 6, 27, and 74 Cards
20.
Find a Pair of 2/3's