1237 and Level 5

Level 5 puzzles always have at least one set of clues with more than one possible common factor. Still only one of those factors will actually work with all the rest of the clues. Can you use logic to find the factors needed to solve this puzzle?

Print the puzzles or type the solution in this excel file: 12 factors 1232-1241

Let’s look at some facts about the number 1237:

  • 1237 is a prime number.
  • Prime factorization: 1237 is prime.
  • The exponent of prime number 1237 is 1. Adding 1 to that exponent we get (1 + 1) = 2. Therefore 1237 has exactly 2 factors.
  • Factors of 1237: 1, 1237
  • Factor pairs: 1237 = 1 × 1237
  • 1237 has no square factors that allow its square root to be simplified. √1237 ≈ 35.17101

How do we know that 1237 is a prime number? If 1237 were not a prime number, then it would be divisible by at least one prime number less than or equal to √1237 ≈ 35.1. Since 1237 cannot be divided evenly by 2, 3, 5, 7, 11, 13, 17, 19, 23, 29 or 31, we know that 1237 is a prime number.

1237 is the sum of two squares:
34² + 9² = 1237

1237 is the hypotenuse of a Pythagorean triple:
612-1075-1237 calculated from 2(34)(9), 34² – 9², 34² + 9²

Here’s another way we know that 1237 is a prime number: Since its last two digits divided by 4 leave a remainder of 1, and 34² + 9² = 1237 with 34 and 9 having no common prime factors, 1237 will be prime unless it is divisible by a prime number Pythagorean triple hypotenuse less than or equal to √1237 ≈ 35.1. Since 1237 is not divisible by 5, 13, 17, or 29, we know that 1237 is a prime number.

1236 and Level 4

V is for victory. Can you be victorious solving this puzzle? Write the numbers from 1 to 12 in both the first column and the top row so that the puzzle functions like a multiplication table with the given clues becoming the products of the factors you write. I’m sure you can do it if you stick with it!

Print the puzzles or type the solution in this excel file: 12 factors 1232-1241

Now I’ll tell you some facts about the number 1236:

  • 1236 is a composite number.
  • Prime factorization: 1236 = 2 × 2 × 3 × 103, which can be written 1236 = 2² × 3 × 103
  • The exponents in the prime factorization are 2, 1, and 1. Adding one to each and multiplying we get (2 + 1)(1 + 1)(1 + 1) = 3 × 2 × 2 = 12. Therefore 1236 has exactly 12 factors.
  • Factors of 1236: 1, 2, 3, 4, 6, 12, 103, 206, 309, 412, 618, 1236
  • Factor pairs: 1236 = 1 × 1236, 2 × 618, 3 × 412, 4 × 309, 6 × 206, or 12 × 103
  • Taking the factor pair with the largest square number factor, we get √1236 = (√4)(√309) = 2√309 ≈ 35.15679

1236 is the sum of consecutive prime numbers three rather interesting ways:

  1. It is the sum of the twenty-two prime numbers from 13 to 103.
  2. It is the sum of the eight prime numbers from 137 to 173.
    (137 + 139 + 149 + 151 + 157 + 163 + 167 + 173 = 1236)
  3. It is also the sum of twin primes: 617 + 619 = 1236

1235 and Level 3

Do you know the greatest common factor of 28 and 35? If you do, then you can solve this puzzle by writing each number from 1 to 12 in both the first column and the top row. Since this is a level 3 puzzle, you can begin with the clues at the top of the puzzle and work your way down cell by cell. Good luck!

Print the puzzles or type the solution in this excel file: 12 factors 1232-1241

Now I’ll share some facts about the number 1235:

  • 1235 is a composite number.
  • Prime factorization: 1235 = 5 × 13 × 19
  • The exponents in the prime factorization are 1, 1, and 1. Adding one to each and multiplying we get (1 + 1)(1 + 1)(1 + 1) = 2 × 2 × 2 = 8. Therefore 1235 has exactly 8 factors.
  • Factors of 1235: 1, 5, 13, 19, 65, 95, 247, 1235
  • Factor pairs: 1235 = 1 × 1235, 5 × 247, 13 × 95, or 19 × 65
  • 1235 has no square factors that allow its square root to be simplified. √1235 ≈ 35.14257

1235 is the hypotenuse of FOUR Pythagorean triples:
304-1197-1235 which is 19 times (16-63-65)
741-988-1235 which is (3-4-5) times 247
627-1064-1235 which is 19 times (33-56-65)
475-1140-1235 which is (5-12-13) times 95

1234 and Level 2

This is my 1234th post, so today’s puzzle has been given that number. Whenever I see 12:34 on a clock, I always think about my husband’s Uncle Paul who really liked noticing that time because all possible clock digits are used and the digits are in order. I also like those digits because 12 = 3 × 4.

Print the puzzles or type the solution in this excel file: 12 factors 1232-1241

Here are some facts about the number 1234 some of which might surprise you:

  • 1234 is a composite number.
  • Prime factorization: 1234 = 2 × 617
  • The exponents in the prime factorization are 1 and 1. Adding one to each and multiplying we get (1 + 1)(1 + 1) = 2 × 2 = 4. Therefore 1234 has exactly 4 factors.
  • Factors of 1234: 1, 2, 617, 1234
  • Factor pairs: 1234 = 1 × 1234 or 2 × 617
  • 1234 has no square factors that allow its square root to be simplified. √1234 ≈ 35.12834

1234 is the sum of two squares:
35² + 3² = 1234

1234 is the hypotenuse of a Pythagorean triple:
210-1216-1234 calculated from 2(35)(3), 35² – 3², 35² + 3²
It is also times (105-608-617)

1233 and Level 1

Perhaps this puzzle is as difficult as a level 1 puzzle can be, but it is still not all that difficult. Nevertheless, if you can solve it, give yourself a big pat on the back.

Print the puzzles or type the solution in this excel file: 12 factors 1232-1241

Here are a few facts about the number 1233:

  • 1233 is a composite number.
  • Prime factorization: 1233 = 3 × 3 × 137, which can be written 1233 = 3² × 137
  • The exponents in the prime factorization are 2 and 1. Adding one to each and multiplying we get (2 + 1)(1 + 1) = 3 × 2  = 6. Therefore 1233 has exactly 6 factors.
  • Factors of 1233: 1, 3, 9, 137, 411, 1233
  • Factor pairs: 1233 = 1 × 1233, 3 × 411, or 9 × 137
  • Taking the factor pair with the largest square number factor, we get √1233 = (√9)(√137) = 3√137 ≈ 35.1141

Look at the numbers in this very cool but square fact about 1233:
12² + 33² = 1233

1233 is the hypotenuse of a Pythagorean triple:
792-945-1233 calculated from 2(33)(12), 33² – 12², 33² + 12²
It is also 9 times (88-105-137)

1232 Factor Cake

1232 is divisible by 2 because it’s even.
It’s divisible by 4 because 32 is divisible by 4
It’s divisible by 8 because 232 is divisible by 8.
It also happens to be divisible by 16 and by 7.
It’s divisible by 11 because 1 – 2 + 3 – 2 = 0

1232 makes a delicious-looking factor cake:

From the factor cake, we see that 2 · 2 · 2 · 2 · 7 · 11 = 1232.

Here’s more about the number 1232:

  • 1232 is a composite number.
  • Prime factorization: 1232 = 2 × 2 × 2 × 2 × 7 × 11, which can be written 1232 = 2⁴ × 7 × 11
  • The exponents in the prime factorization are 4, 1 and 1. Adding one to each and multiplying we get (4 + 1)(1 + 1)(1 + 1) = 5 × 2 × 2 = 20. Therefore 1232 has exactly 20 factors.
  • Factors of 1232: 1, 2, 4, 7, 8, 11, 14, 16, 22, 28, 44, 56, 77, 88, 112, 154, 176, 308, 616, 1232
  • Factor pairs: 1232 = 1 × 1232, 2 × 616, 4 × 308, 7 × 176, 8 × 154, 11 × 112, 14 × 88, 16 × 77, 22 × 56, or 28 × 44
  • Taking the factor pair with the largest square number factor, we get √1232 = (√16)(√77) = 4√77 ≈ 35.09986

The odd prime factors of 1232 are 7 and 11.
OEIS.org informs us that (7 × 8 × 9 × 10 × 11) / (7 + 8 + 9 + 10 + 11) = 1232

1231 Mystery Level Puzzle

For almost all the sets of clues in this puzzle, there is more than one permissible common factor. That makes the puzzle a little tricky, but with care, you can still solve it using logic and your knowledge of the basic 10×10 multiplication table. Good luck!

Print the puzzles or type the solution in this excel file: 10-factors-1221-1231

Now I’ll tell you a little bit about the number 1231:

  • 1231 is a prime number.
  • Prime factorization: 1231 is prime.
  • The exponent of prime number 1231 is 1. Adding 1 to that exponent we get (1 + 1) = 2. Therefore 1231 has exactly 2 factors.
  • Factors of 1231: 1, 1231
  • Factor pairs: 1231 = 1 × 1231
  • 1231 has no square factors that allow its square root to be simplified. √1231 ≈ 35.08561

How do we know that 1231 is a prime number? If 1231 were not a prime number, then it would be divisible by at least one prime number less than or equal to √1231 ≈ 35.1. Since 1231 cannot be divided evenly by 2, 3, 5, 7, 11, 13, 17, 19, 23, 29 or 31, we know that 1231 is a prime number.

1231 is a palindrome in a couple of bases:
It’s A1A in BASE 11 because 10(11²) + 1(11) + 10(1) = 1231, and
it’s 1B1 in BASE 30 because 1(30²) + 11(30) + 1(1) = 1231

1230 Mystery

Is this mystery level puzzle easy or difficult? The only way to know for sure is to start filling in the factors. Don’t guess and check. Use logic to find its unique solution!

Print the puzzles or type the solution in this excel file: 10-factors-1221-1231

Here is some information about the number 1230:

1230 ends with a zero so it is divisible by 2 and 5.
It is a number formed by three consecutive numbers and a zero so it is divisible by 3.

  • 1230 is a composite number.
  • Prime factorization: 1230 = 2 × 3 × 5 × 41
  • The exponents in the prime factorization are 1, 1, 1, and 1. Adding one to each and multiplying we get (1 + 1)(1 + 1)(1 + 1)(1 + 1) = 2 × 2 × 2 × 2 = 16. Therefore 1230 has exactly 16 factors.
  • Factors of 1230: 1, 2, 3, 5, 6, 10, 15, 30, 41, 82, 123, 205, 246, 410, 615, 1230
  • Factor pairs: 1230 = 1 × 1230, 2 × 615, 3 × 410, 5 × 246, 6 × 205, 10 × 123, 15 × 82, or 30 × 41
  • 1230 has no square factors that allow its square root to be simplified. √1230 ≈ 35.07136

1230 is the hypotenuse of four Pythagorean triples:
270-1200-1230 which is 30 times (9-40-41)
504-1122-1230 which is 6 times (84-187-205)
738-984-1230 which is (3-4-5) times 246
798-936-1230 which is 6 times (133-156-205)

 

1229 and Level 6

The only common factors permitted for 32 and 40 in this puzzle are 4 and 8, but which one will work for this puzzle? Likewise, you must decide if 3 or 6 is the right common factor for 18 and 30. Don’t guess which factor to use. Study the other clues and let logic guide your decisions until the unique solution is found. Have fun with this one!

Print the puzzles or type the solution in this excel file: 10-factors-1221-1231

This is my 1229th post, so I will tell you a little bit about the number 1229:

  • 1229 is a prime number.
  • Prime factorization: 1229 is prime.
  • The exponent of prime number 1229 is 1. Adding 1 to that exponent we get (1 + 1) = 2. Therefore 1229 has exactly 2 factors.
  • Factors of 1229: 1, 1229
  • Factor pairs: 1229 = 1 × 1229
  • 1229 has no square factors that allow its square root to be simplified. √1229 ≈ 35.057

How do we know that 1229 is a prime number? If 1229 were not a prime number, then it would be divisible by at least one prime number less than or equal to √1229 ≈ 35.1. Since 1229 cannot be divided evenly by 2, 3, 5, 7, 11, 13, 17, 19, 23, 29 or 31, we know that 1229 is a prime number.

1229 is the sum of three consecutive prime numbers:
401 + 409 + 419 = 1229

1229 is the sum of two square numbers:
35² + 2²  = 1229

1229 is the hypotenuse of a primitive Pythagorean triple:
140-1221-1229 calculated from 2(35)(2), 35² – 2², 35² + 2²

Here’s another way we know that 1229 is a prime number: Since its last two digits divided by 4 leave a remainder of 1, and 35² + 2² = 1229 with 35 and 2 having no common prime factors, 1229 will be prime unless it is divisible by a prime number Pythagorean triple hypotenuse less than or equal to √1229 ≈ 35.1. Since 1229 is not divisible by 5, 13, 17, or 29, we know that 1229 is a prime number.

 

1228 and Level 5

This level 5 puzzle has a row and a column with the exact same two clues. That ISN’T a good place to start this puzzle! Nevertheless, you can solve it, if you use logic and your knowledge of a basic 10 × 10 multiplication table. There is only one solution. Good luck!

Print the puzzles or type the solution in this excel file: 10-factors-1221-1231

Now I’ll share some information about the number 1228:

  • 1228 is a composite number.
  • Prime factorization: 1228 = 2 × 2 × 307, which can be written 1228 = 2² × 307
  • The exponents in the prime factorization are 2 and 1. Adding one to each and multiplying we get (2 + 1)(1 + 1) = 3 × 2  = 6. Therefore 1228 has exactly 6 factors.
  • Factors of 1228: 1, 2, 4, 307, 614, 1228
  • Factor pairs: 1228 = 1 × 1228, 2 × 614, or 4 × 307
  • Taking the factor pair with the largest square number factor, we get √1228 = (√4)(√307) = 2√307 ≈ 35.04283

1228 is repdigit 444 in BASE 17 because 4(17² + 17 + 1) = 4(307) = 1228