The Proof! tabletop card game is the inspiration behind our online game, the Weekly Challenge Math Puzzles. Each week we post a new set of nine cards that hides a challenging equation. This is a hand-picked selection of our trickier math puzzles that might involve some out-of-the-box thinking. Or see all of our math puzzles here.

JAN 29 2018

5

Find a Triplet of 7's

Using At Least 7 Cards

FEB 12 2018

7

Find Any Triplet of

Fractions

FEB 26 2018

9

Find Any Pair

Greater Than

MAR 26 2018

13

Find Any Pair Using All

9 Cards

APR 02 2018

14

Find Any Quadruplet

APR 09 2018

15

Find Any Triplet Less Than

0

APR 23 2018

17

Find a Quadruplet of 1's

APR 30 2018

18

Find Any Pair Using At

Least 3 Square Roots

MAY 14 2018

20

Find a Pair of 2/3's

MAY 21 2018

21

Find 10 Different Quadruplets

Less Than 10

JUN 04 2018

23

Find Any Quintuplet

JUL 16 2018

29

Find a Pair of 1000's

AUG 20 2018

34

Find a Pair of 667/1271's

AUG 27 2018

35

Find 7 Different Pairs

Greater Than 15 Using

SEP 03 2018

36

Find Any Pair Greater

Than 0 Using All 9 Cards

SEP 24 2018

39

Find a Pair of 18's

Using Only Subtraction

OCT 08 2018

41

Find a Pair of 10000's

OCT 15 2018

42

Find 5 Different Quintuplets

Greater Than 0

OCT 22 2018

43

Find Any Pair Less Than

100 Using All 9 Cards

NOV 19 2018

47

Find Any Pair Greater

Than 0 Using All 9 Cards

DEC 17 2018

51

Find a Pair of 1's

Using Only Division

DEC 31 2018

53

Find a Pair of 2019's