Saturday, March 16, 2019

KenKen Puzzle Number 27 - 5x5 Normal Level


This is a normal difficulty 5x5 puzzle from the free Mathdoku App that you can download and use on your phone or tablet.  This free app provides endless different puzzles of all sizes and levels of difficulty and has many interesting features

The Washington Post provides a version you can do online through your browser:    

 And here is   

KenKen Puzzle Number 26 - 5x5 Normal Level

This is a normal difficulty 5x5 puzzle from the free Mathdoku App that you can download and use on your phone or tablet.  This free app provides endless different puzzles of all sizes and levels of difficulty and has many interesting features.

The Washington Post provides a version you can do online through your browser:    

 And here is   

Sunday, March 10, 2019

KenKen Puzzle Number 25 - 5x5 Normal Level



NOTE:  This begins a series of normal difficulty 5x5 puzzles which are excellent as a daily puzzle that is challenging but not too difficult or time consuming.  
 
This is a normal difficulty 5x5 puzzle from the free Mathdoku App that you can download and use on your phone or tablet.  This free app provides endless different puzzles of all sizes and levels of difficulty and has many interesting features.

The Washington Post provides a version you can do online through your browser:    


 And here is   

Thursday, December 13, 2018

Puzzle Solution Index

 INDEX OF PUZZLES AND SOLUTIONS 

Not familiar with KenKen puzzles?  Learn all about them at the

 KenKen Puzzle Introduction with Sherlock Holmes

Once you understand the puzzle you can see how some simple logical deduction can be applied to these problems:

Beginners can also check their calculations with a variety of free online...


There are many free online versions of KenKen appearing under other names:
 


The solved puzzles:

These puzzles are listed in order from easiest to hardest (Puzzles 1-22).  

Puzzles 23 and 24 are 5x5 Puzzles with some interesting strategies used for their solution.

Puzzles 25-30 are a series of 5x5 normal difficulty puzzles that are excellent as a daily puzzle that is not too difficult or time consuming.  This series should be helpful for beginners who want some example solutions.

Puzzles 31 begins a series of 6x6 normal difficulty puzzles that are more challenging than the 5x5s. 

Puzzle 37 begins a series of 7x7 normal difficulty puzzles that increase the challenge.

     
    Series of 5x5 Normal Level Puzzles



  • KenKen Puzzle Number 25: 5x5 Normal Level 
  •  

  • KenKen Puzzle Number 26: 5x5 Normal Level 




  • KenKen Puzzle Number 27: 5x5 Normal Level 




  • KenKen Puzzle Number 28: 5x5 Normal Level 




  • KenKen Puzzle Number 29: 5x5 Normal Level 




  • KenKen Puzzle Number 30: 5x5 Normal Level 

  •  

    Series of 6x6 Normal Level Puzzles



  • KenKen Puzzle Number 31: 6x6 Normal Level 




  • KenKen Puzzle Number 32: 6x6 Normal Level




  • KenKen Puzzle Number 33: 6x6 Normal Level




  • KenKen Puzzle Number 34: 6x6 Normal Level  




  • KenKen Puzzle Number 35: 6x6 Normal Level




  • KenKen Puzzle Number 36: 6x6 Normal Level


    Series of 7x7 Normal Level Puzzles




  • KenKen Puzzle Number 37: 7x7 Normal Level




  • KenKen Puzzle Number 38: 7x7 Normal Level




  • KenKen Puzzle Number 39: 7x7 Normal Level




  • KenKen Puzzle Number 40: 7x7 Normal Level




  •  KenKen Puzzle Number 41: 7x7 Normal Level




  •  KenKen Puzzle Number 42:7x7 Normal Level




  •  KenKen 6x6 Puzzles to Solve Without Using Scratch Paper
  • Monday, September 3, 2018

    KenKen Calculators for Factoring and Checking Possibilities

    A number of KenKen calculators and solvers are available online.  One useful one for beginners is:

    CalcuDoku, Killer Sudoku and Kakuro calculator!


    If you are a beginner and uneasy about factoring and establishing all possible cage solutions, then you can use this calculator to check to see if you have found all the possibilities for solving a cage.  We present the following example using the 48x cage from Problem 24 in this blog:


    Above is the 48x cage.  For the 5x5 puzzle we see that four numbers are required between 1 and 5.  We also note that 3 doubles (or repeats of the same number) are possible:  on the two sets of diagonal squares as well as in the top and bottom squares.  This gives us enough information to plug into the above online calculator:

     Once we have plugged in these values, we press the calculate button and generate the answer:


     We see that this yields the same values that we established in the puzzle solution note:

    We can look at another example, this time the 432x cage from Problem 22 in this blog:
                  

    This is a 9x9 puzzle and there is one possible double (or repeat of the same number) on the diagonal.  This is enough information to enter into the calculator:

     We press calculate and see the single result:


    If we want to figure this out logically, without the calculator we start by breaking down 432 to its prime factors:

    2 x 2 x 2 x 2 x 3 x 3 x 3

     We can see right away that 1 cannot be used, since 1x9x9 (the maximum number solution) is nowhere near 432!  We must now multiply some of these numbers together so that we are left with three numbers from the set 1 through 9. 

    If we start at the low end and convert 2x2 into 4, we are left with 2x2x3x3x3 and there is no way to make two numbers under 10 from these factors.  If we start with 2x2x2=8 then we are left with 2x3x3x3 and we can see only one way to combine these into two numbers we can use:  2x3=6 and 3x3=9.  So we get the single possibility: 6x8x9.

    We can work through a similar argument starting from 3 at the high end of these factors and arrive at the same conclusion: 6x8x9.


    FACTORING HELP

    For those who merely want help factoring a large number, there are a number of straight factoring calculators available.  Remember, however that 1 is always a factor and is often used.  One good calculator is:

    from Calculator.Net
    If you plug in 432 from the above example you get the following result that breaks down the factors in several different ways.  For KenKen solvers, the PRIME FACTORS are the important ones since they give you the base to work out what possibilities can be used for any particular cage:





    Sunday, August 12, 2018

    KenKen Puzzle Number 24: Using a tree diagram to clarify the logic

    In this puzzle we employ a tree diagram for the first time to see the logical possibilities more clearly.  The 3 on top can combine with 2 or 4 in a 1- cage, and we can show how these possibilities combine with other numbers in a column to arrive at the column total of 15.  Check out the solution below to see this tree diagram at work!




    Monday, July 30, 2018

    KenKen Puzzle Number 23: Interesting row summing logic in a hard 5x5 Puzzle

    This 5x5 puzzle at the hard level offers some interesting row summing logic that lets us use the top row to crack the whole puzzle open.  Recall that for the 5x5 puzzles, each row and column must total 15 and contain the numbers: 1,2,3,4,5.


    KenKen 6x6 Puzzles to Solve Without Scratch Paper

    Lately I have been challenging myself to solve 6x6 puzzles without using scratch paper for factoring or other figuring.  Below is a link to ...