DAY 169:

Today’s Challenge

Three unique digits from 1-9 must be used to arrive at a specified target number. This is done by multiplying two of these numbers together and either adding or subtracting the third unique number to arrive at your target. Today’s target number is 18.

By using the formula (a×b)±c, where a b and c are three unique digits from 1-9, one way of arriving at 18 is (5×4)2.  Find the other FOUR ways it is possible to make 18.

[Note:  (5×4)–2 = 18 and (4×5)2 = 18  counts as just ONE way.]

The 7puzzle Challenge

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

The 2nd & 7th rows contain the following fourteen numbers:

4    8    11    17    24    27    28    30    48    55    63    64    70    77

Which number above 20 becomes a multiple of 11 when 20 is subtracted from it?

Make 169 Challenge

Can you arrive at 169 by inserting 10, 11, 12 and 13 into the gaps below?

◯×(◯+◯–◯) = 169

Answers can be found here.

Click Paul Godding for details of online math tuition. Wherever you are in the world, please get in touch.

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DAY 168:

Today’s Challenge

The two sections below both contain eight letters, A-H. Each letter has an addition calculation attached, all involving 2-digit numbers.

Which is the only letter that has exactly the same answer in both sections?

  • Section 1

D:68+18   B:51+14   E:47+31   H:62+32   A:44+29   G:59+25   C:36+23   F:38+26

  • Section 2

E:64+28   A:31+27   F:34+22   B:43+19   G:48+36   C:54+16   D:48+21   H:50+38

The 7puzzle Challenge

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

The 2nd & 7th rows contain the following fourteen numbers:

4    8    11    17    24    27    28    30    48    55    63    64    70    77

Which three different numbers have a total which is also present on the list?

Make 168 Challenge

Can you arrive at 168 by inserting 2, 2, 6 and 16 into the gaps below?

(◯–◯)×◯×◯ = 168

Answers can be found here.

Click Paul Godding for details of online math tuition. Wherever you are in the world, please get in touch.

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DAY 167:

Today’s Challenge

The rules of Kakuro are very simple.

Just like a crossword, fill in the boxes. Each box must contain a number from 1-9. Each run of boxes must add up to the total shown on the left or above.  You cannot use the same digit in each run, so if a total of 4 is to be completed in 2 boxes, they must be made up of either 3+1 or 1+3, but not 2+2.

Try this beginner puzzle:

The 7puzzle Challenge

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

The 2nd & 7th rows contain the following fourteen numbers:

4    8    11    17    24    27    28    30    48    55    63    64    70    77

How many multiples of 7 are listed?

Make 167 Challenge

Can you arrive at 167 by inserting 2, 10, 14 and 16 into the gaps below?

(◯×◯)+(◯÷◯) = 167

Answers can be found here.

Click Paul Godding for details of online math tuition. Wherever you are in the world, please get in touch.

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DAY 166:

Today’s Challenge

This number trail has seven arithmetical steps.  Start with the number 49, then:

√      add nineteen      50% of this      2      +26      subtract nine      ÷7      =      ?

What is your final answer?

The 7puzzle Challenge

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

The 2nd & 7th rows contain the following fourteen numbers:

4    8    11    17    24    27    28    30    48    55    63    64    70    77

What is the sum of the factors of 24?

Make 166 Challenge

Can you arrive at 166 by inserting 4, 7, 14 and 17 into the gaps below?

(◯×◯)+(◯×◯) = 166

Answers can be found here.

Click Paul Godding for details of online math tuition. Wherever you are in the world, please get in touch.

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DAY 165:

Today’s Challenge

In this Kakuro-type question, can you list the only THREE ways of making 18 when adding together five unique digits from 1-9?

The 7puzzle Challenge

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

The 4th & 6th rows contain the following fourteen numbers:

3    5    10    12    18    20    32    33    35    44    49    54    56    60

What is the sum of the factors of 120?

Make 165 Challenge

Can you arrive at 165 by inserting 5, 10, 15 and 20 into the gaps below?

(◯+◯)×◯–◯ = 165

Answers can be found here.

Click Paul Godding for details of online math tuition. Wherever you are in the world, please get in touch.

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DAY 164:

Today’s Challenge

You have 12 balls and each ball is numbered differently from 1 to 12.  They are randomly placed into two bags so each contains six numbered balls as shown below:

  • Red bag: 2, 3, 4, 6, 9, 11
  • Blue bag: 1, 5, 7, 8, 10, 12

You then move a ball from the red bag to the blue bag.  The total of the seven balls in the blue bag is now double the total of the five balls left in the red bag.

Which ball did you move from the red bag to the blue bag?

The 7puzzle Challenge

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

The 4th & 6th rows contain the following fourteen numbers:

3    5    10    12    18    20    32    33    35    44    49    54    56    60

How many pairs of numbers have a difference of 12?

Answers can be found here.

Click Paul Godding for details of online math tuition. Wherever you are in the world, please get in touch.

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DAY 163:

Today’s Challenge

The concept behind this challenge is similar to my MATHELONA number puzzles, so please feel free to click the link for details of my popular pocket book of challenges.

Replace all 15 ◯’s below with the numbers 1-15, once each, so all five lines work out:

◯   +   ◯   =   ◯
◯   +   ◯   =   ◯
◯   +   ◯   =   ◯
◯   +   ◯   =   ◯
◯   +   ◯   =   ◯

The 7puzzle Challenge

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

The 4th & 6th rows contain the following fourteen numbers:

3    5    10    12    18    20    32    33    35    44    49    54    56    60

What is the sum of the consecutive numbers listed?

The 7puzzle Challenge

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

The 4th & 6th rows contain the following fourteen numbers:

3    5    10    12    18    20    32    33    35    44    49    54    56    60

How many pairs of numbers have a difference of 12?

Answers can be found here.

Click Paul Godding for details of online math tuition. Wherever you are in the world, please get in touch.

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DAY 162:

Today’s Challenge

Here’s a mini-MATHELONA challenge where you must replace the eight ◯’s below with the eight digits 0, 1, 1, 2, 2, 2, 3 and 4 so both lines work out arithmetically:

◯  +  ◯   =    4    =   ◯  ×  ◯
◯  –  ◯   =    2    =   ◯  ÷  ◯

Click MATHELONA for details of our pocket book challenges.

The 7puzzle Challenge

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

The 4th & 6th rows contain the following fourteen numbers:

3    5    10    12    18    20    32    33    35    44    49    54    56    60

Which two numbers, when each is divided by 6, also appear on the list?

Answers can be found here.

Click this link for details of online math tuition with me, Paul Godding.

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DAY 161:

Today’s Challenge

Three unique digits from 1-9 must be used in a particular way to arrive at a specified target number. The rule is to multiply two numbers together, then either add or subtract the third number, so you arrive at today’s target number of 30.

As an example, one such way of making 30 is (8×3)+6. Can you find the other FOUR ways of making 30?

[Note:  (8×3)+6 = 30  and  (3×8)+6 = 30  counts as just ONE way]

The 7puzzle Challenge

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

The 4th & 6th rows contain the following fourteen numbers:

3    5    10    12    18    20    32    33    35    44    49    54    56    60

How many square numbers are listed?

Answers can be found here.

Click this link for details of online math tuition with me, Paul Godding.

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DAY 160:

Today’s Challenge

Read the following five clues and work out which number I am today:

  • I am a 2-digit number
  • My 1st digit is bigger than my 2nd digit
  • I am less than 50
  • I am an odd number
  • I am not a prime number

The 7puzzle Challenge

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

The 1st & 5th rows contain the following fourteen numbers:

2     6     7     9     14     15     16     21     22     40     50     72     81     84

Which of the multiples of 10 has more factors?

Answers can be found here.

Click this link for details of online math tuition with me, Paul Godding.

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