Step-by-Step Solution

for Friday 12th September Diabolical

Number 5 is the only value possible in cell (9,3).

Single Candidate

For row 8, number 9 is only possible in cell (2,8)

Single Position

For column 7, Number 9 is only possible in cell (7,2)

Single Position

Number 1 is the only value possible in cell (9,1).

Single Candidate

Number 2 is the only value possible in cell (9,9).

Single Candidate

Number 9 is the only value possible in cell (9,4).

Single Candidate

For column 8, Number 8 is only possible in cell (8,1)

Single Position

For row 5, number 4 is only possible in cell (2,5)

Single Position

For row 7, number 5 is only possible in cell (6,7)

Single Position

For row 4, number 2 is only possible in cell (8,4)

Single Position

For row 7, number 2 is only possible in cell (3,7)

Single Position

For row 2, number 1 is only possible in cell (3,2)

Single Position

For row 2, number 4 is only possible in cell (6,2)

Single Position

For row 2, number 2 is only possible in cell (4,2)

Single Position

For row 8, number 2 is only possible in cell (6,8)

Single Position

Naked Pair for 6 and 7, can remove these as candidates from other cells.

Naked Pairs

Hidden Pair for 3 and 8, can remove other candidates from these cells.

Hidden Pairs

For row 6, number 5 is only possible in cell (2,6)

Single Position

Number 1 is the only value possible in cell (2,4).

Single Candidate

Number 5 is the only value possible in cell (4,4).

Single Candidate

Number 6 is the only value possible in cell (1,6).

Single Candidate

Number 4 is the only value possible in cell (1,1).

Single Candidate

Number 7 is the only value possible in cell (3,4).

Single Candidate

Number 6 is the only value possible in cell (6,4).

Single Candidate

Number 6 is the only value possible in cell (2,9).

Single Candidate

Number 7 is the only value possible in cell (2,1).

Single Candidate

Number 4 is the only value possible in cell (3,8).

Single Candidate

For row 5, number 6 is only possible in cell (8,5)

Single Position

For row 9, number 4 is only possible in cell (7,9)

Single Position

Either candidate for cell (6,1) forces 1 into cell (5,5).

Forcing Chains

For blocks 5 and 8, candidates for 7 are all in the same two columns (4 and 6)

Double Pairs

Either candidate for cell (8,2) forces 8 into cell (5,7).

Forcing Chains

Number 1 is the only value possible in cell (1,7).

Single Candidate

Number 6 is the only value possible in cell (7,7).

Single Candidate

Number 8 is the only value possible in cell (1,9).

Single Candidate

For row 3, number 8 is only possible in cell (4,3)

Single Position

Number 3 is the only value possible in cell (4,6).

Single Candidate

Number 8 is the only value possible in cell (6,6).

Single Candidate

Either candidate for cell (5,2) forces 6 into cell (5,8).

Forcing Chains

Number 1 is the only value possible in cell (4,8).

Single Candidate

Number 3 is the only value possible in cell (7,8).

Single Candidate

Number 7 is the only value possible in cell (7,3).

Single Candidate

Number 3 is the only value possible in cell (8,2).

Single Candidate

Number 7 is the only value possible in cell (5,2).

Single Candidate

Number 3 is the only value possible in cell (5,3).

Single Candidate

Number 9 is the only value possible in cell (6,1).

Single Candidate

Number 6 is the only value possible in cell (4,1).

Single Candidate

Number 3 is the only value possible in cell (3,1).

Single Candidate

Number 6 is the only value possible in cell (3,3).

Single Candidate

Number 7 is the only value possible in cell (6,5).

Single Candidate

Number 9 is the only value possible in cell (4,5).

Single Candidate

Number 1 is the only value possible in cell (7,6).

Single Candidate

Number 7 is the only value possible in cell (8,6).

Single Candidate

Number 7 is the only value possible in cell (4,9).

Single Candidate

Number 3 is the only value possible in cell (6,9).

Single Candidate

Number 1 is the only value possible in cell (8,9).

Single Candidate