DAY/DYDD/GIORNO/NAP 322:

The Main Challenge

You have the same starting number and final answer, both 32, with lots of arithmetical steps in between, but the 10th step is missing! What should it be if it involves an integer?

Start with the number 32, then:

5  ÷9  +4  ×3  ÷2  ×5  5  ÷2   ?   ×2  +4  ÷3  ×2  =  32

For the real number puzzle enthusiast, there is another possible step which involves a decimal number. What is it?

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 1st & 7th columns contain the following fourteen numbers:

5   9   13   21   22   24   27   28   32   50   55   56   60   66

Which multiple of 7, when adding 1 to it, becomes a prime number?

The Factors Challenge

Which is the ONLY number below that is a factor of 322?

4    6    8    10    12    14    16    18

The Mathematically Possible Challenge

Using 56 and 12 once each, with + – × ÷ available, which is the ONLY number it is possible to make from the list below?

4    8    12    16    20    24    28    32    36    40

#4TimesTable

The Target Challenge

Can you arrive at 322 by inserting 6, 7, 8, 9 and 10 into the gaps below?

  •  (◯²×(◯–◯)+◯)×◯ = 322

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 321:

The Main Challenge

Our unique Mathematically Possible question asks you to consider three different combinations of numbers by using each number once each with + – × ÷ available:

  •   2   6   10
  •   3   7   10
  •   4   8   10

What is the ONLY target answer from 10-30 that can be made by ALL three combinations?

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 5th & 6th columns contain the following fourteen numbers:

7   8   11   14   18   25   30   36   40   44   49   54   64   84

How many more square numbers are listed than cube numbers?

The Factors Challenge

Which of the numbers below are factors of 321?

3    5    7    9    11    13    None of them

The Mathematically Possible Challenge

Using 56 and 12 once each, with + – × ÷ available, which FOUR numbers is it possible to make from the list below?

3    6    9    12    15    18    21    24    27    30

#3TimesTable

The Target Challenge

Can you arrive at 321 by inserting 13, 4, 7 and 8 into the gaps below?

  •  (◯+◯)××◯+◯ = 321

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 320:

The Main Challenge

In this particular number puzzle, three UNIQUE digits from 1-9 must be used to arrive at a specified target number; today is 42.

The formula is always the same; multiply two numbers together, then either add or subtract a third number to achieve your target.

One way to make 42 is (9×4)+6; can you find the only other TWO ways of making 42?

[Note:  (9×4)+6 and (4×9)+6 counts as just ONE way.]

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 5th & 6th columns contain the following fourteen numbers:

7   8   11   14   18   25   30   36   40   44   49   54   64   84

What is the difference between the highest and lowest multiples of 4?

The Factors Challenge

Which SIX numbers below are factors of 320?

2    4    6    8    10    12    14    16    18    20

The Mathematically Possible Challenge

Using 47 and 11 once each, with + – × ÷ available, which is the ONLY number it is possible to make from the list below?

100   101   102   103   104   105   106   107   108   109

#Numbers100to109

The Target Challenge

Can you arrive at 320 by inserting 10, 20, 30, 40 and 50 into the gaps on each line below?

  •  ◯×◯×(◯–◯)÷◯ = 320
  •  (◯+◯)×◯÷(◯–◯) = 320
  •  (÷)× = 320

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 319:

The Main Challenge

Apart from 8+3+2+1, list the FOUR other ways of making 14 when adding together four unique digits from 1-9 in our latest Kakuro-type challenge.

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 3rd & 4th columns contain the following fourteen numbers:

3   4   6   12   15   17   20   35   42   63   72   77   80   81

Which pair of numbers have a sum of 50?

The Factors Challenge

Which is the ONLY number below that is a factor of 319?

3    5    7    9    11    13    15    17    19

The Mathematically Possible Challenge

Using 47 and 11 once each, with + – × ÷ available, which are the only TWO numbers it is possible to make from the list below?

70    71    72    73    74    75    76    77    78    79

#NumbersIn70s

The Target Challenge

Can you arrive at 319 by inserting 2, 3, 4, 6 and 12 into the gaps below?

  •  ((◯+◯)×◯)²–(◯–◯)² = 319

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 318:

The Main Challenge

Using the numbers 2, 5 and 10 once each, with + – × ÷ available, which ELEVEN target numbers from 1-30 are mathematically possible to achieve?

This is a number puzzle associated with our popular board game, Mathematically Possible, an excellent resource involving mental arithmetic and strategy. Click the above link for full details.

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 3rd & 4th columns contain the following fourteen numbers:

3   4   6   12   15   17   20   35   42   63   72   77   80   81

What is the difference between the square roots of the two square numbers shown above?

The Factors Challenge

Which TWO numbers below are not factors of 318?

1      2      3      4      5      6

The Mathematically Possible Challenge

Using 47 and 11 once each, with + – × ÷ available, which is the ONLY number it is possible to make from the list below?

50    51    52    53    54    55    56    57    58    59

#NumbersIn50s

The Target Challenge

Can you arrive at 318 by inserting 1, 2, 4, 9 and 10 into the gaps below?

  •  (◯+◯)²+(◯+◯)²+◯ = 318

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 317:

The Main Challenge

Here is a number puzzle similar in concept to my FlagMath card game. Many schools are now playing the various editions, so here’s a taster:

Each of the eight letters, A-H, in the two sections contain a calculation with an answer in the 20’s:

  • Section 1

B:84÷4   G:296   C:3515   D:14+10   A:5×5   H:72÷3   E:7×4   F:16+11

  • Section 2

H:15+12   B:348   F:9×3   E:48÷2   C:11×2   G:60÷3   A:17+12   D:4015

Which is the only letter that has the SAME answer in BOTH sections?

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 1st & 2nd columns contain the following fourteen numbers:

2   10   13   16   21   22   27   33   45   48   55   56   60   70

How many of the above become prime numbers when 10 is added to them?

The Factors Challenge

Which of the following numbers are factors of 317?

3    5    7    9    11    13    15    17    None of them

The Mathematically Possible Challenge

Using 47 and 11 once each, with + – × ÷ available, which are the THREE numbers it is possible to make from the list below?

30    31    32    33    34    35    36    37    38    39

#NumbersIn30s

The Target Challenge

Can you arrive at 317 by inserting 7, 8, 9, 10 and 11 into the gaps below?

  •  ◯×◯×◯+◯×◯ = 317

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 316:

The Main Challenge

One from our range of Mathelona number puzzles now available in pocket book format. Your task is to make all three lines work out arithmetically by filling the 12 gaps with the following numbers:

0     0     1     1     2     2     2     2     4     5     6     7

Can you successfully complete this?

◯  +  ◯   =    6    =   ◯  –  ◯
◯  +  ◯   =    2    =   ◯  ×  ◯
◯  +  ◯   =    7    =   ◯  ÷  ◯

Full details of our pocket book can be found by clicking Mathelona.

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 1st & 2nd columns contain the following fourteen numbers:

2   10   13   16   21   22   27   33   45   48   55   56   60   70

What is the sum of the multiples of 11 listed above?

The Factors Challenge

Which is the ONLY number below that is a factor of 316?

3      4      5      6      7      8      9

The Mathematically Possible Challenge

Using 47 and 11 once each, with + – × ÷ available, which is the ONLY number it is possible to make from the list below?

2    3    5    7    11    13    17    19    23    29

#PrimeNumbers

The Target Challenge

Can you arrive at 316 by inserting 2, 4, 5, 6 and 7 into the gaps below?

  •  ◯²×◯²–◯×◯×◯ = 316

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 315:

The Main Challenge

Try this 10-step number trail involving the four arithmetical operations and all the numbers from 1 to 10.

Start off with the number 27, then:

  •  divide by 3
  •  subtract 1
  •  multiply by 6
  •  add 2
  •  ÷10
  •  +8
  •  –9
  •  ×4
  •  add 5
  •  ÷7

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 2nd & 5th rows contain the following fourteen numbers:

6   7   8   16   17   21   28   48   50   55   63   64   81   84

How many multiples of 5 are listed?

The Factors Challenge

Which TWO of the following numbers are not factors of 315?

3     5     7     9     11     13     15

The Mathematically Possible Challenge

Using 47 and 11 once each, with + – × ÷ available, which FOUR numbers is it possible to make from the list below?

1    4    9    16    25    36    49    64    81    100

#SquareNumbers

The Target Challenge

Can you arrive at 315 by inserting 1357 and 9 into the gaps below?

  •  (+)²×double◯+◯×◯ = 315

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 314:

The Main Challenge

Today’s task using the excellent, addictive American maths card game 24game is to try and arrive at the target answer of 24 from each of the following seven groups of numbers. In each calculation, all four digits must be used exactly once each, with + – × ÷ available.

But it is impossible to reach 24 with one of these seven groups:

  •    2    2    2    3
  •    2    2    2    4
  •    2    2    2    5
  •    2    2    2    6
  •    2    2    2    7
  •    2    2    2    8
  •    2    2    2    9

Which one?

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 2nd & 5th rows contain the following fourteen numbers:

6   7   8   16   17   21   28   48   50   55   63   64   81   84

What is the sum of the multiples of 7?

The Factors Challenge

Which of the following numbers are factors of 314?

4    6    8    10    12    14    16    18    None of them

The Mathematically Possible Challenge

Using 47 and 11 once each, with + – × ÷ available, which are the only TWO numbers it is possible to make from the list below?

11    22    33    44    55    66    77    88    99    110

#11TimesTable

The Target Challenge

Can you arrive at 314 by inserting 4, 9, 16, 25 and 36 into the gaps below?

  •  (◯+◯)×(◯–◯)–◯ = 314

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY/DYDD/GIORNO/NAP 313:

The Main Challenge

Consider the four groups of numbers 3 3 3, 4 4 4, 5 5 5 and 6 6 6.

There are only six target numbers it is possible to make in the range 10-30 when + – × ÷ is available to use.

One of these is 12, which can be made by doing either 3×3+3 or 4+4+4. Can you find the other FIVE target numbers it is possible to make using one or more of these four groups?

The 7puzzle Challenge

The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.

The 2nd & 5th rows contain the following fourteen numbers:

6   7   8   16   17   21   28   48   50   55   63   64   81   84

Which number is the product of two other numbers on the list?

The Factors Challenge

Which of the following numbers are factors of 313?

3     7     9     11     13     17     19     None of them

The Mathematically Possible Challenge

Using 47 and 11 once each, with + – × ÷ available, which are the only TWO numbers it is possible to make from the list below?

9    18    27    36    45    54    63    72    81    90

#9TimesTable

The Target Challenge

Can you arrive at 313 by inserting 1, 3, 5, 7 and 9 into the gaps below?

  •  ◯³–(◯–◯)×◯×◯ = 313

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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