Step-by-Step Solution

for Thursday 19th February Fiendish

For row 3, number 5 is only possible in cell (7,3)

Single Position

For row 7, number 5 is only possible in cell (3,7)

Single Position

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

Single Position

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

Single Position

For column 5, Number 2 is only possible in cell (5,2)

Single Position

For column 6, Number 2 is only possible in cell (6,7)

Single Position

For column 8, Number 2 is only possible in cell (8,1)

Single Position

For row 3, number 9 is only possible in cell (9,3)

Single Position

For row 2, number 7 is only possible in cell (8,2)

Single Position

For row 1, number 7 is only possible in cell (3,1)

Single Position

For row 1, number 8 is only possible in cell (6,1)

Single Position

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

Single Position

For row 9, number 1 is only possible in cell (8,9)

Single Position

For column 5, Number 3 is only possible in cell (5,8)

Single Position

For column 8, Number 3 is only possible in cell (8,7)

Single Position

For box 3, Number 6 is only possible in cell (9,2)

Single Position

Number 4 is the only value possible in cell (6,2).

Single Candidate

Number 3 is the only value possible in cell (4,2).

Single Candidate

For box 8, candidates for 9 are all in column 4, so you can remove candidates from other blocks.

Candidate Lines

For box 9, candidates for 4 are all in row 7, so you can remove candidates from other blocks.

Candidate Lines

For box 9, candidates for 6 are all in column 7, so you can remove candidates from other blocks.

Candidate Lines

For blocks 3 and 9, candidates for 4 are all in the same two columns (7 and 9)

Double Pairs

Candidates for 1 in boxes 4 and 6 force the candidates in box 5 to be in the remaining line.

Multiple Lines

Candidates for 4 in boxes 5 and 6 force the candidates in box 4 to be in the remaining line.

Multiple Lines

Candidates for 6 in boxes 2 and 8 force the candidates in box 5 to be in the remaining line.

Multiple Lines

Naked Pair for 6 and 8, can remove these as candidates from other cells.

Naked Pairs

Number 4 is the only value possible in cell (8,5).

Single Candidate

Number 6 is the only value possible in cell (8,4).

Single Candidate

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

Single Candidate

Number 1 is the only value possible in cell (9,4).

Single Candidate

Number 6 is the only value possible in cell (3,5).

Single Candidate

Number 8 is the only value possible in cell (5,5).

Single Candidate

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

Single Candidate

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

Single Candidate

Number 7 is the only value possible in cell (1,4).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 1 is the only value possible in cell (4,5).

Single Candidate

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

Single Candidate

Number 1 is the only value possible in cell (6,3).

Single Candidate

Number 9 is the only value possible in cell (6,5).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 4 is the only value possible in cell (2,8).

Single Candidate

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

Single Candidate

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

Single Candidate

Number 4 is the only value possible in cell (1,3).

Single Candidate

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

Single Candidate

Number 9 is the only value possible in cell (1,7).

Single Candidate

Number 8 is the only value possible in cell (4,7).

Single Candidate

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

Single Candidate

Number 3 is the only value possible in cell (9,1).

Single Candidate

Number 4 is the only value possible in cell (7,1).

Single Candidate

Number 8 is the only value possible in cell (9,6).

Single Candidate

Number 3 is the only value possible in cell (7,6).

Single Candidate

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

Single Candidate

Number 7 is the only value possible in cell (4,8).

Single Candidate

Number 2 is the only value possible in cell (1,9).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 8 is the only value possible in cell (7,9).

Single Candidate