DAY 351:

The Main Challenge

This is perhaps a bit trickier than you think!  Add these four numbers together and write your answer in words:

  •  Two hundred and four thousand and nine,
  •  Seventy thousand, nine hundred and eight,
  •  Four hundred and fifty thousand and seventy,
  •  One hundred and seven thousand, three hundred and ninety-five.

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 4th & 5th columns contain the following fourteen numbers:

3   6   8   11   14   18   20   25   42   44   63   72   77   84

How many numbers listed are NOT multiples of 3, 5 or 7?

The Factors Challenge

Which THREE of the numbers below are factors of 351?

3    5    7    9    11    13    15    17    19

The Mathematically Possible Challenge

Using 13 and once each, with + – × ÷ available, which is the ONLY number it is possible to make from the list below?

10    20    30    40    50    60    70    80    90    100

#10TimesTable

The Target Challenge

Can you arrive at 351 by inserting 1, 2, 3, 4 and 5 into the gaps on each line?

  •  (◯+◯)²×double◯–(◯×◯)² = 351
  •  (◯–◯)³×(◯×◯–◯) = 351

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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CROESO

A warm Welsh welcome, or Croeso, to 7puzzleblog.com and our compendium of daily number puzzles.

Five challenges are posted each day, seven days a week, and designed for our many followers from nearly 170 countries & territories throughout the world.

As well as our ever-expanding website of arithmetical challenges, this is also the place to learn about our successful venture into maths tuition.

The World’s #1 Daily Number Puzzle Website

When typing daily number puzzles into top search engines such as Google, BingYahoo, Baido, DuckDuckGo and Ecosia, you’ll see 7puzzleblog.com officially listed at #1 each time.

We appreciate and value your continued support.

Our aim

Simply to help improve basic knowledge and confidence of arithmetic in a fun way. Start your numerical adventure by trying to solve today’s five number puzzles.

How to use our website

As well as our latest challenges, simply access the remainder of our number puzzles by continually scrolling down the page.

Alternatively, to retrieve and attempt any particular day’s challenges from the past 12 months, just type in the address bar:

  •  7puzzleblog.com/1 for DAY 1, through to . . .
  •  7puzzleblog.com/366 for DAY 366

The Challenges

We have a vast collection of number puzzles, the majority of which are our very own creations and are in seven categories:

The Main Challenge – involving different types of number puzzle gathered from all parts of the globe and will vary in content and difficulty from one day to the next.

The 7puzzle Challenge – linked to our signature puzzle board game, this is generally the easiest of the five daily number puzzles. Great for younger or less-confident students and will also improve their knowledge of mathematical terminology.

The Roll3Dice Challenge (DAYS 1 to 10) – puzzlers will be given seven groups of three numbers which replicate the rolling of three dice. The numbers in six of these groups will be able to arrive at the target number, but your task is to find the impossible group!

The Lagrange Challenge (DAYS 11 to 250) – named after the French-Italian mathematician who proved that every positive whole number can be made from adding together up to four square numbers. A medium-difficulty challenge where puzzlers must arrive at that particular day’s target number using his theorem.

The Factors Challenge (DAYS 251 to 366) – again related to that particular day’s number, puzzlers have to find which of the numbers listed, if any, are factors of the number in question (it will divide exactly into it). Good practice for ‘bus-stop’ division, and great to test some of the mathematical tricks available to find whether our number is a multiple of 2, 3, 4, 5 . . . and so on.

The Mathematically Possible Challenge – based on our best-selling arithmetic board game and designed to encourage creative number work. Challenges are also at the medium level of difficulty, but may require perseverance to find the possible answers!

The Target Challenge – hardest of the challenges, puzzlers must insert the given numbers into the correct gaps to arrive at the day’s target number. Can sometimes be tricky but will satisfy greatly when solved. A knowledge of BIDMAS, indices and estimation is desirable, but it will also help to think logically.

Copyright

We always encourage our number puzzles to be printed out for both fun and educational purposes in schools, home or work, but no part of this website may be republished or transmitted without prior permission and accreditation.

Puzzles & answers: Copyright © Paul Godding.

Spread the message

We’d really appreciate it if you could inform family, friends, students and colleagues about our fabulous daily number puzzles at 7puzzleblog.com. Please tell them there is no fee or registration required to access them, but most importantly that answers are provided!

You can get in touch by sending tweets to @7puzzle and e-mails to paul@7puzzle.com.

We hope you enjoy your visit.

Author, Paul Godding

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DAY 350:

The Main Challenge

This involves one of our favourite puzzles, Kakuro, which is all about addition and number combinations. Your task is to find different ways of making 29 when adding together six UNIQUE digits from 1-9.

One such way is 9+8+6+3+2+1; can you list the other SEVEN ways?

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 4th & 5th columns contain the following fourteen numbers:

3   6   8   11   14   18   20   25   42   44   63   72   77   84

Which two numbers add to make a square number greater than 100?

The Factors Challenge

Which of the numbers below are factors of 350?

5    10    15    20    25    30    35    40    45    50

The Mathematically Possible Challenge

Using 13 and once each, with + – × ÷ available, which THREE numbers is it 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 350 by inserting 10, 20, 30, 40 and 50 into the gaps below?

  •  ◯×(◯+◯)÷(◯–◯) = 350

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY 349:

The Main Challenge

Using the numbers 4, 4 and 8 once each, with + – × ÷ available, what is the lowest whole number it is not possible to achieve?

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 & 3rd columns contain the following fourteen numbers:

2   4   10   12   15   16   17   33   35   45   48   70   80   81

How many pairs of numbers have a sum of 50?

The Factors Challenge

Which of the numbers below are factors of 349?

3    5    7    9    11    13    15    17    19    None of them

The Mathematically Possible Challenge

Using 13 and once each, with + – × ÷ available, which is the ONLY number it is possible to make from the list below?

8    16    24    32    40    48    56    64    72    80

#8TimesTable

The Target Challenge

Can you arrive at 349 by inserting 6, 7, 8, 9 and 10 into the gaps below?

  •  (◯²+◯²)׳√◯–(◯+◯) = 349

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY 348:

The Main Challenge

This number puzzle is based on the concept of my FlagMath series of card games. Here is an example of a typical challenge in the Multiplication edition.

Each of the nine letters, A-I, in the two sections below contains a multiplication calculation. Which is the only letter to have the SAME answer in BOTH sections?

  • Section 1

E:9×4   H:6×5   G:8×2   A:6×4   D:10×2   I:4×3   F:5×2   B:8×3   C:7×5

  • Section 2

F:6×6   I:9×3   A:5×3   H:4×4   C:3×3   E:8×2   B:7×4   D:5×4   G:10×3

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 & 3rd columns contain the following fourteen numbers:

2   4   10   12   15   16   17   33   35   45   48   70   80   81

Find the square root of each of the square numbers listed above. What is their sum?

The Factors Challenge

Which FIVE numbers below are factors of 348?

2    3    4    5    6    7    8    9    10    11    12

The Mathematically Possible Challenge

Using 13 and once each, with + – × ÷ available, which are the only TWO numbers it is possible to make from the list below?

7    14    21    28    35    42    49    56    63    70

#7TimesTable

The Target Challenge

Can you arrive at 348 by inserting 2, 3, 4, 5 and 6 into the gaps on both lines below?

  •  (◯²+◯²)×(◯²÷◯+◯) = 348
  •  (×◯+◯)×ײ = 348

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY 347:

The Main Challenge

How many 3-digit numbers contain at least two 7’s?

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 4th & 7th columns contain the following fourteen numbers:

3   5   6   9   20   24   28   32   42   50   63   66   72   77

Which FIVE numbers become prime numbers when 5 is added to each of them?

The Factors Challenge

Which numbers below are factors of 347?

3    5    7    9    11    13    None of them

The Mathematically Possible Challenge

Using 13 and once each, with + – × ÷ available, which SIX numbers is it possible to make from the list below?

6    12    18    24    30    36    42    48    54    60

#6TimesTable

The Target Challenge

Can you arrive at 347 by inserting 2, 4, 5, 10 and 20 into the gaps below?

  •  ◯²–◯²–◯×(◯+◯) = 347

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY 346:

The Main Challenge

This is a problem-solving question from a typical Eleven Plus exam many years ago. Can today’s generation solve it?

Twice one hundred and sixty-eight added to four times another number gives a total of four hundred and eighty. What is the other number?

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 4th & 7th columns contain the following fourteen numbers:

3   5   6   9   20   24   28   32   42   50   63   66   72   77

Which two numbers above, when multiplied by 7, have their answers appearing on the list?

The Factors Challenge

Which numbers below are factors of 346?

4    6    8    10    12    14    16    18    None of them

The Mathematically Possible Challenge

Using 13 and once each, with + – × ÷ available, which are the only TWO numbers it is possible to make from the list below?

5    10    15    20    25    30    35    40    45    50

#5TimesTable

The Target Challenge

Can you arrive at 346 by inserting 1, 2, 3, 4 and 5 into the gaps below?

  •  ◯³×◯(+)²–² = 346

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY 345:

The Main Challenge

A gentle logic puzzle for all members of the family to try.

The nine numbers, 1-9, must be placed into the 3-by-3 grid by following these rules:

  • 1 is in the top right-hand corner
  • 3 and 8 are also in the top row
  • 2 is in the middle row, left-hand side
  • 4 and 6 are both in the bottom row
  • 8 and 7 are in the left-hand column
  • 6 and 9 are in the right-hand column

x              x               x

x              x               x

x              x               x

Can you now insert the numbers 1-9, once each, into the correct places?

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 & 6th columns contain the following fourteen numbers:

7   13   21   22   27   30   36   40   49   54   55   56   60   64

Find three pairs of numbers that each total 43.

The Factors Challenge

Which FOUR numbers below are factors of 345?

3    5    7    9    11    13    15    17    19    21    23    25

The Mathematically Possible Challenge

Using 13 and once each, with + – × ÷ available, which FIVE numbers is it 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 345 by inserting 5, 10, 15, 20 and 25 into the gaps on each line below?

  •  (+÷√◯)×(◯+◯) = 345
  •  (+◯)×◯–◯÷◯ = 345

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY 344:

The Main Challenge

Can you find the 4-digit number that has all these properties?

  •  its second digit is twice the first,
  •  its fourth digit is three times the third,
  •  all its digits are different,
  •  no two of its digits are consecutive.

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 & 6th columns contain the following fourteen numbers:

7   13   21   22   27   30   36   40   49   54   55   56   60   64

Which two numbers, when each is doubled, also appear on the list?

The Factors Challenge

Which numbers below are factors of 344?

2     3     4     5     6     7     8     9

The Mathematically Possible Challenge

Using 13 and once each, with + – × ÷ available, which THREE numbers are NOT 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 344 by inserting 1, 2, 3, 4 and 5 into the gaps below?

  •  ◯⁵+◯×◯²+◯–◯ = 344

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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DAY 343:

The Main Challenge

Follow the rules and eliminate every number, except one.

From the numbers 1-50, eliminate:

  • all numbers containing 1, 3, 5 or 7
  • even numbers
  • square numbers

There is just one number left, 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 3rd & 5th columns contain the following fourteen numbers:

4   8   11   12   14   15   17   18   25   35   44   80   81   84

What is the difference between the highest multiples of 8 and 9?

The Factors Challenge

Which is the ONLY number below that is a factor of 343?

3    5    7    9    11    13    15    17    19

The Mathematically Possible Challenge

Using 29 and 12 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 343 by inserting 1, 2, 3, 4 and 5 into the gaps on each line below?

  •  (◯+◯+◯–◯–◯)³ = 343
  •  (◯×◯×◯–◯×◯)³ = 343

Answers can be found here.

Click Paul Godding for details of online maths tuition.

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