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Sudoku XV puzzles and instructions

Play free Sudoku XV puzzles:
 2nd Aug   Sudoku XV 387 22nd Jul   Sudoku XV 385 6th May   Sudoku XV 369 30th Apr   Sudoku XV 368
Sudoku XV puzzles add extra constraints to regular Sudoku puzzles, labelling all pairs of neighbouring squares which contain values which add up to either 5 or 10 using the Roman numerals 'V' for 5 and 'X' for 10.

How to solve Sudoku XV puzzles
A Sudoku XV puzzle consists of a standard Sudoku grid with the addition of X and V markers between neighbouring pairs of squares. X markers show all adjacent pairs of squares where the two values in those squares add up to 10, while V markers show all pairs where the two values sum to 5.

To solve Sudoku XV you must place 1 to 9, or 1 to whatever the size of the puzzle is, once each into every row, column and bold-lined rectangle while also obeying the X and V markers.

It's really important to note that all possible pairs which sum to either 5 or 10 are marked, so if there is no 'v' and no 'x' then two squares do not sum to either 5 or 10.

Look at the top-right of the solved puzzle on the left. The 1 and 4 sum to 5, so there is a 'v' between them. Meanwhile at the top-left the 6 and 4 sum to 10 and so have an 'x' between. Conversely the 3 and 6 at the top-left sum to neither 5 nor 10 and so have no symbol between them.

Every Sudoku XV puzzle only ever has one possible solution, and it can always be reached via reasonable logical deduction. In other words, guessing is never required.

Sudoku XV puzzles on puzzlemix appear at a wide range of sizes and difficulties. Usually they are 6x6, 8x8 or 9x9, in which case you must place 1-6, 1-8 or 1-9 once each into every row, column and bold-lined rectangle. These bold-lined rectangles are 2x3 for 6x6 puzzles, 4x2 for 8x8 puzzles and they are 3x3 for 9x9 puzzles.

Other types of puzzle
It's not just Sudoku XV you can solve online at puzzlemix. You can also solve logic puzzles that include these:

Keywords
Are you searching for help with Sudoku XV puzzles? Stuck on solving Sudoku XV? Don't know the instructions for Sudoku XV? Need Sudoku XV instructions? Want solving hints and tips for Sudoku XV? Then puzzlemix is the place for you to play Sudoku XV puzzles online.

Looking for printed Sudoku XV puzzles? Visit Sudoku Xtra for puzzle magazines and books.

Or are you looking for a Sudoku XV puzzle supplier? If so then check out Any Puzzle Media, my puzzle production company.

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