jasen

_ + _ = _ _ + _ = _ _ + _ = _ _ + _ = _ Fill the blanks with numbers above, so: The 4 equations are right. All numbers must be used. If we turn the equations upside down, they are still right. You can rotate any numbers too, example 1091 -> 1601.

When creating this puzzle (using computer), I started with 3 first constraints, then I got many solutions, so I have to add 1 more constraint. But I have to keep the symmetry of the puzzle. First I tried to sum the three corners, but I still got some solutions. Then I tried to product the three corners, which yields 1 unique solution. When creating this puzzle (using computer), I started with 3 first constraints, then I got many solutions, so I have to add 1 more constraint. But I have to keep the symmetry of the puzzle. First I tried to sum the three corners, but I still got some solution

Replace letters with numbers 1 to 9, so the 3 operations below are equals. Each letter represents one unique number. ab / c = de * f = gh - i Note : If a = 1, and b = 2, then ab = 12 NOT multiplication It is more fun if you solve this without computer, trust me this is easy.

based on this @bonanova puzzle, I create another similar puzzle You are given the following ten statements and are asked to determine a particular number. At least one of statements 7 and 8 is true. This either is the first true or the first false statement. The number is a prime number. The first true statement multiplied by the last false statement divides the number. The number of divisors of the number is greater than the sum of the numbers of the true statements. The number has exactly 4 prime divisors. The number is bigger than 1000. T

yes there are still 2 more solution.

Yes you are right, each operator only can be used once. making ((9!)(6!))/3 cases. (Because of the symmetry)

Note : A # B = A*10 + B Arrange the numbers 1 to 9 to green triangles, and arrange operator (+,-,x,/,^, and #) to the white triangles, so the math operations below are equals. (((A op1 B) op2 D) op4 F) = constant (((F op4 G) op5 H) op6 I) = constant (((I op6 E) op3 C) op1 A) = constant A x F x I = constant

No, you can choose the robot in each step something like 2213232.....

8 very poisonous substances named s1 to s8 are kept in a safety room. The substances are kept in ascending order (s1,s2,s3,s4,s5,s6,s7 and s8). In the room there are 3 robots. First robot can "rotate left" the order of the substances. If the order is (a,b,c,d,e,f,g,h) the robot will make it (b,c,d,e,f,g,h,a) Second robot can split the substances into 2 part then reverse the order of each part. If the order is (a,b,c,d,e,f,g,h) the robot will make it (d,c,b,a,h,g,f,e) But the robot is a bit broken, so the resulting order is a bit wrong. The resulting order will become (d,c

It is possible, I have it. I will show it next week if nobody find it until 10 Nov 2016.

151 131 359 131 151 \ ^ ^ ^ / 131 < 1 3 1 > 131 353 < 3 5 3 > 353 191 < 1 9 1 > 191 / V V V \ 151 131 953 131 151 This 3x3 table have an interesting properties. Every direction (up,down, Right, Left, 45°,135°,225°,315°) of 3 cell form prime numbers. There are 6 unique prime numbers from this table, they are 131, 151, 191, 353, 359, 953. Create a more interesting 3x3 table with the same rule, which there are 9 unique prime numbers from the table.

Example : a---b---c / \ / \ d e f g / \ / \ h---i---j---k---l \ / \ / m n o p \ / \ / q---r---s a+b+c = a+e+j = c+f+j = 23, and so on.... Note : There are 2 solutions, if we rule out reflections and rotations. Bonus Puzzle : How if all the rows of 3 numbers between O (big o) sums to 22,24,25,26,27,28,29,31,32,33,34,35,36, 37, and 38. I have checked all the solutions by computer, and all those sums have solutions.

[0,1,6,4,3] [4,5,6,0,9] [9,9,0,1,1] [1,0,4,5,6] [7,6,4,9,0] This 5x5 table has unique properties. Each number in a cell means : or Here is another example [0,1,6,4,8] [1,2,1,3,2] [1,0,9,0,1] [4,5,6,0,4] [4,5,1,0,9] [6,5,9,5,6] [4,4,0,6,6] [3,3,0,7,7] [5,5,0,5,5] [1,0,4,5,1] [1,0,9,5,6] [9,0,1,0,9] [2,1,4,4,0] [8,7,9,8,9] [4,5,1,5,4] What surprised me is, every table like this will follow this : I have checked this with my computer. Why this happens ?

Solve this alphametic ENLIST + SILENT + LISTEN = ANAGRAM Leading zero is ok. There is only 1 solution.