Solutions

Problem of the Month

Twin Primes

1. The next greater twin prime pair after 29 and 31 is 41 and 43.
2. The numbers between twin pairs greater than 3 are all multiples of 6 because only numbers one more or one less than 6n can be prime. 6n + 2 and 6n + 4 are even numbers, and 6n + 3 is divisible by 3.

Bonus Q: 6n – 1, 6n + 1, 6n + 5, and 6n + 7 could represent two pair of twin primes as close as could be. The primes 5, 7, 11, and 13 are one example. Can you find another?

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Posers

Numbered Pentominoes

Challenge #25 Use TUFLNY

Some advice on this one and others. In a 6x5 puzzle there will be six pieces. The total of the entire grid is 90, and so the "magic sum" per piece is 15. Work from each corner. Sum five in a row across if the I-piece is allowed, and check for 15. It is NOT customary to have the I-tile divide the grid into two pieces. Next check four in a row plus one other for a sum of 15. You may find the Y or the L usable, as they are on the left and right sides here. These are tough puzzles. Practice doesn't always make perfect. I know.

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Target Practice Plus

Challenge 1. 172 = (14 + 4) x 10 + 22 – 30; also 172 = (10 – 4) x 30 + 14 – 22.

Using just four numbers, 172 = (44 x 4) + 10 – 14. Other solutions exist.

Challenge 2. 35 = (60 / 4) + (225 / 75) + 17; also 35 = (225 / 75) + 17 + 11 + 4

Challenge 3. 241 = (29 x 11) – 75 – 3.

other solutions possible.

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Department of Words

Ferriswords

From left to right find DUPLEX.

From right to left find ENCASE.

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Five and Ten

Puzzle 1. Cantaloupe      Puzzle 2. Providence

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Fit for Four

1. west   2. final    3. level    4. bone

5. half    6. hard    7. card    8. fast

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Crisscross Crunch

Across, in row order: offer, ferrous, user; byline, never, verse; knitter, terse, sera; starve, veal, algae; snood, odd, doodad.

Down, in column order: iffy, F.Y.I., instant; debit, bitter, error; orb, beveled, eddy; lure, easel, seldom; lens, stream, mad.

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Minicryptic 7s5s3s

Across 1. Cumulus ( three u's)    4. Ravel (anagram Laver)    7. Eco (anagram)    

8. Ruddy (Rudy + d)    9. High-end (two definitions)

Down 1. Carwash (crash + aw)    2. Mover (shaker go-with)    3. Strayed (anagram)

5. Ecu (e + Cu)    6. Lodge (two definitions)

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