MY criteria for level 5 puzzles is that they require noticing two pairs or two doubles (but NOT chains or coloring).
Therefore, in solving, I attempt to exhaust all naked singles, hidden singles, single-line eliminations, and double-line eliminations.Sometimes, I will repeat the puzzle when it is partially done at this point.
PB Post 2014 01 03 Lvl 5
PB Post 2014 01 10 Lvl 5
PB Post 2014 01 17 Lvl 5
Jan 19. Lots of Pairs. Good puzzle. Stopped several times, but finish.
Repeated lower with pinks filled in.
PB Post 2014 01 19 Sunday Lvl 5 Same puzzle as above except the pink boxes are filled in.
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Note underlined tiny numbers can be eliminated. In columns C and D 2/9 pair. In column E 3/5 pairs. When 31 left, I found B2=6 because columns A & C claimed by 6 in two lower groups.
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Here is a rigorous Level 5 puzzle. Requires detecting many PAIRS of "doubles" / "pairs"
PB Post 2014 01 26 Sunday Lvl 5
PB Post 2014 01 31 Lvl 5
Required about 2 pairs to solve.
PB Post 2014 02 02 Sunday (Repeated lower down)
While I used coloring to eliminate some 1's, I don't know if it was necessary. Lots of eliminations based on finding two pairs in a "zone". Took a LONG TIME to enter a 9 anywhere!
PB Post 2014 02 02 Sunday This is the same puzzle as above except the green boxes are filled in.
(Note: Using "simple" methods, the 18 underlined numbers can be removed as choices.)
In order to proceed, I used colors and multicolors. I don't know if that was all necessary. For colors, I used 1 and discovered that C4 could not contain 1.
Then I continued using colors for 1. I used MULTI-COLORS for it, and found that G4 could not equal 1. I wrote myself a hint about next checking to eliminate 6's.
PB Post 2014 02 07 Lvl 5 (4) is posted with Level 4 puzzles.
PB Post 2014 02 09 Sunday Lvl 5 (6) is posted with Level 6 puzzles.
PB Post 2014 02 14 Lvl 5 (6) is posted with Level 6 puzzles.
PB Post 2014 02 16 Sunday Lvl 5
Like any good level 5, this required finding two pairs many times. Finished quickly.
PB Post 2014 02 21 Lvl 5
Almost a Level 4, except with 34 remaining, I used doubles that allowed me to find the 9 in column D.
PB Post 2014 02 28 Lvl 5
PB Post 2014 03 14 w 44 Same puzzle as above except the green boxes are filled in.
(See note at top of this page explaining criteria for showing a puzzle such as this one, partially completed)
(Note: Using "simple" methods, the underlined 5 in C5 can be removed as a choice.)
To proceed with 44, in Column D, find two 5/7 "doubles" which allows some eliminations.
In column G find two 3/5 pairs, then 4/9 pairs. This leaves H5 with the only 4 in its group. FINIS!
PB Post 2014 03 16 Lvl 5 (Repeated lower down)
A good, rigorous Level 5 puzzle.
The ease of the blue boxes is pretty arbitrary. This author CHOSE to refrain from using pairs or doubles while filling in those 9 blue boxes. There is absolutely no reason for others to follow such a choice.
I found lots of single-line and double-line eliminations.
PB Post 2014 03 16 w 45 Same puzzle as above except the green boxes are filled in.
Note: Using "simple" methods, the 17 underlined numbers (rows 1, 7, 8, and 9) can be removed as a choices.
PB Post 2014 03 21 Lvl 5
[The following is merely comment on how the author solved. Users might go about it in a different order, resulting in totally different obstacles and solutions.]
Lots of naked singles began the puzzle. 7 was the first number to be filled in completely.
With 39 remaining, in Group 1, two 2/5 hidden doubles allows some eliminations. Keep checking for pairs and doubles along the top 3 rows for more.
With 33 remaining, in Column H two 8/9 doubles prove that H9 cannot be 8, so H9 = 5.
With 26 remaining, in Group 9, 8/9 doubles prove that I8 = 2.
It was still a struggle to finish, but eventually....FINIS.
PB Post 2014 04 06 Lvl 5 (Repeated lower down)
Notable puzzle because... Hidden triple. Sadly, not required!
User might get beyond pink boxes because of 1/5 doubles found in Group 7. But it's good to read explanation below the 2nd showing of this puzzle. It is an example of a "hidden" triple.
PB Post 2014 04 06 w 37 Same puzzle as above except the pink boxes are filled in.
Easiest solution is noticing Group 7, 1/5 doubles means that A7 cannot be a 1 or a 5. That leaves G7 as the only 1 in its row. Then in Group 9, 2/5 doubles mean that I8 cannot be 5, and so equals 9. FINIS.
NOTE AN ALTERNATE METHOD starts with the same 1/5 double in Group 7 allowing you to eliminate 1 from A7, But then, in row 7, recognize a "hidden" triple. The 2/7 , 5/7, and 2/5 doubles represent only 3 values available for 3 boxes. Therefore, 2, 5, and 7 can be eliminated from OTHER boxes in row 7. This proves that A7 =8. FINIS
PB Post 2014 03 16 Lvl 5 (Repeated lower down)
A good, rigorous Level 5 puzzle.
The ease of the blue boxes is pretty arbitrary. This author CHOSE to refrain from using pairs or doubles while filling in those 9 blue boxes. There is absolutely no reason for others to follow such a choice.
PB Post 2014 03 16 w 45 Same puzzle as above except the green boxes are filled in.
Users may have already noted many things listed here:
To proceed with 45 in puzzle above, in Grp 1 there are 1/3 pairs and 5/8 pairs.
Grp 2 has 3/7 pairs. Col A has 2/6 pairs, then 5/9 doubles.The 8 in A6 became the only one in Col A.
With 44 Col F has 3/7 pairs. Also in Column F 5/9 doubles imply F7 cannot be 9 and must be 6.
The final 43 answers were naked singles!
To proceed with 45 in puzzle above, in Grp 1 there are 1/3 pairs and 5/8 pairs.
Grp 2 has 3/7 pairs. Col A has 2/6 pairs, then 5/9 doubles.The 8 in A6 became the only one in Col A.
With 44 Col F has 3/7 pairs. Also in Column F 5/9 doubles imply F7 cannot be 9 and must be 6.
The final 43 answers were naked singles!
PB Post 2014 03 21 Lvl 5
Lots of naked singles began the puzzle. 7 was the first number to be filled in completely.
With 39 remaining, in Group 1, two 2/5 hidden doubles allows some eliminations. Keep checking for pairs and doubles along the top 3 rows for more.
With 33 remaining, in Column H two 8/9 doubles prove that H9 cannot be 8, so H9 = 5.
With 26 remaining, in Group 9, 8/9 doubles prove that I8 = 2.
It was still a struggle to finish, but eventually....FINIS.
PB Post 2014 03 23 Sun Lvl 5
Pretty easy. I needed a pair only one time: in row 5, I used a 5/9 pair to eliminate other numbers.Curiously, that 5/9 pair was available after my very first entry, the naked single 9 in H5. (I didn't notice it until I had filled in about 20 naked and hidden singles.)
Multiple alternatives undoubtedly avoid this use of that pair.
PB Post 2014 03 30 Sun Lvl 5
[The following is merely comment on how the author solved. Users might go about it in a different order, resulting in totally different obstacles and solutions.]
Medium Level 5
With 45 remaining, I found - in column A - that I could eliminate 1's in one group. Thne I made use of 1/6 pairs, and of 4/8 pairs in Column A.
Later, with 42 remaining, I found - in Column E - 5/8 pairs, then 1/3 pairs (which revealed E6=9)
Medium Level 5
With 45 remaining, I found - in column A - that I could eliminate 1's in one group. Thne I made use of 1/6 pairs, and of 4/8 pairs in Column A.
Later, with 42 remaining, I found - in Column E - 5/8 pairs, then 1/3 pairs (which revealed E6=9)
Do the 7s first. Fast.
Green boxes required simplest techniques, but other users might easily fill other boxes in. The partially completed puzzle is repeated below for new Level 5 learners.
PB Post 2014 04 04 w 46 Same puzzle as above except the green boxes are filled in.
[The following is merely comment on how the author solved. Users might go about it in a different order, resulting in totally different obstacles and solutions.]
The UNDERLINED possibilities above were eliminated by several techniques.
In Group 3, notice the two 2/3 pairs which allows OTHER possibilities in I1 and I2 to be eliminated.
In Group 5, notice that 1's in the two adjoining groups (4 & 6) are only found in ROWS 4 & 6. Thus, Group 5 must contain a 1 in row 5, eliminating other 1s in group 5.
Looking at the possibilities for 8 in columns G and I leads to crossing them out of those two columns in Group 3.
While other method will work, interesting to note in Group 5, the 1/6/8 triple in row 5 of that groups allows elimination of 8 from E4 and F4. (Other method: single row of 8's in Group 6).
(MAYBE some answers got filled in?) but I soon used a 4/5 double found in group 3.
Solution followed pretty soon afterwards.
PB Post 2014 04 06 Lvl 5 (Repeated lower down)
Notable puzzle because... Hidden triple. Sadly, not required!
PB Post 2014 04 06 w 37 Same puzzle as above except the pink boxes are filled in.
Easiest solution is noticing Group 7, 1/5 doubles means that A7 cannot be a 1 or a 5. That leaves G7 as the only 1 in its row. Then in Group 9, 2/5 doubles mean that I8 cannot be 5, and so equals 9. FINIS.
NOTE AN ALTERNATE METHOD starts with the same 1/5 double in Group 7 allowing you to eliminate 1 from A7, But then, in row 7, recognize a "hidden" triple. The 2/7 , 5/7, and 2/5 doubles represent only 3 values available for 3 boxes. Therefore, 2, 5, and 7 can be eliminated from OTHER boxes in row 7. This proves that A7 =8. FINIS
Had many hidden pairs. Average Level 5.
PB Post 2014 04 25 Lvl 5
The comments here may not reflect the user's experience, since they depend on the order of finding answers.
At first, a naked 5 and a naked 3 were found.
Then ALL of the 8's were easily filled in.
With 37 remaining, in Row 5 I found a 1/3 double, allowing some eliminations.
In GROUP 3, a (hidden) pair of 3/7's allowed me to eliminate and prove that I3 =4, then I9 = 2, A1 = 2.
Eventually finished.
PB Post 2014 04 27 Sun Lvl 5
Felt like cheating, but I had computer program highlight pairs after only one naked single was found. In group 1, there was a 1/7 pair, and in group 7 there was a 4/5 pair. These allowed eliminations that apparently made the puzzle easy. FINIS
PB Post 2014 05 01 Lvl 4 (5)
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Newspaper calls this a Level 4, but I used (perhaps not required) double-line elimination of 9's (in Gp 9, then Gp 8). Stubborn puzzle. I call it a Level 5
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PB Post 2014 05 09 Lvl 5
I first found two 2's, then a 4.
Seven naked singles
In group 3, 1/5 pairs allowed some eliminations.
In ROW 7, 3/7 pairs allowed eliminations and resulted in D9=6.
All the 2's were then filled in.
Naked singles finished the puzzle.
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Notice Group 7: Single-line elimination of 8s.
Column F: single-line elimination of 5
Row 9: 5/8 doubles
Column F: 1/6 doubles
Group 2: 5/9 doubles
.....
Later on, Group 4: single-line elimination of 1
Row 5: Hidden 1/6 pair
Column G: Hidden 2/4 pair
Group 6: 1/3/6 triple proves G4 = 8.
Eventually finish.
PB Post 2014 05 23 Lvl 5
Here's my order of solving. Users may successfully solve in a totally different fashion:
No naked singles to start!
I found a 1, 6, two 7s, two 9s, then a 5, two 6's.
With all the green boxes filled in, there were 46 remaining. See next puzzle:
PB Post 2014 05 23 w 46 Same puzzle as above except the green boxes are filled in.
With 46 remaining:
In group 6, hidden 6/8 pairs allowed some eliminations.
Then, in row 4, a 2/3/5 triple proved that D4 = 7.
After that, two more 7s
In group 1, vertical double-line elimination of 3's
Row 5: single-line elimination of 5s.
Then 6 naked singles.
Then a 5, a 6, two 8s, and finally a slew of naked singles to finish.
PB Post 2014 05 26 Sun Lvl 5
Good Level 5 puzzle.
My chronicle: 2 naked singles.
Then three 1s, 2, 4,
Column C: single-line elimination of 5s.
6
Row 6: Single line eliminations of 8
9, 7, 2
Row 6: Sinlge line eliminations of 3, then of 4, then triple 1/6/8 proves that A6 = 5
Row 5: 5/6 double
Row 1: 4/7 pair proves G1 =3
8 naked singles
2, 3
29 naked singles FINIS
PB Post 2014 06 01 Sunday Lvl 5
Repeated lower with green filled in.
Green boxes do not require hidden pairs, nor double-line eliminations.
Chronicle:
I found a 4;
Then in Column B, single-line eliminations of 5
Then two 8s, two 9s, an 8
Column D: 1/2 double allows eliminations proving D6=3
Row 7: Single line eliminations of 2
Then three 3s.
Then 5 naked singles.
That left me with the next view:
PB Post 2014 06 01 Sunday Lvl 5 w 38 Same puzzle as above except the green boxes are filled in.
To continue from here, with 38 to go:
In rows 1 and 2: double-line eliminations of 1
Then I found a 2, 4, two 5s.
Rows 4 and 6 allowed double-line eliminations of 2
Then I filled in two 2s before completing with 32 naked singles.
PB Post 2014 06 05 Lvl 4 (5)
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Chronical of my solution. User may go about it differently.
2, five (all) 4s, four (all) 6s, 7, 1, three 2s
Three naked singles
3
With 34: Column F's: single-line elimination of 3s
Rows 7 and 8: double-line elimination of 7 proves that B9 = 3 (earned the level 5 designation)
Row 8: Single-line elimination of 9s;
Row 2: Single-line elimination of 1 proves C3 = 1;
32 naked singles.
2, five (all) 4s, four (all) 6s, 7, 1, three 2s
Three naked singles
3
With 34: Column F's: single-line elimination of 3s
Rows 7 and 8: double-line elimination of 7 proves that B9 = 3 (earned the level 5 designation)
Row 8: Single-line elimination of 9s;
Row 2: Single-line elimination of 1 proves C3 = 1;
32 naked singles.
PB Post 2014 06 08 Sunday Lvl 5 (Repeated lower down)
A good, rigorous Level 5 puzzle.
Advanced users might easily fill in boxes that are not shaded green. Green boxes do not require hidden pairs, but some single and double-line eliminations were employed.
PB Post 2014 06 08 Sunday w 37 Same puzzle as above except the green boxes are filled in.
Using "simple" methods ... NOT requiring hidden singles... the 14 underlined possibilities can be eliminated.
To continue after that, I first noted in Column C there was a "hidden" 1/3 pair. I'm not sure that was necessary.
Next I found Row 6 a hidden 6/8 pair. This allowed me to determine that F6 = 7.
36 naked singles finished the puzzle.
PB Post 2014 06 13 Lvl 5
The comments here may not reflect the user's experience, since they depend on the order of finding answers.
13 naked singles
4
Row 1 / Group 1: 1/2 double allows eliminations
Column A: 5/6 double leads to two naked singles: 7 and 4
Then a 7 then two 1s.
Group 1: 6/7 double produces eliminations.
Finally: in Group 1, a 3/8 pair allows eliminations.
Soon a 9 is found, then a 5.
And 34 naked singles finish the puzzle.
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