At the 7puzzle company, we produce regular number puzzles for our many followers from 114 different countries (at the last count) around the world. Our aim is to help improve people’s basic knowledge and confidence of number & arithmetic in a fun way.
Enjoy your visit and spread the message about the fabulous number puzzles at 7puzzleblog.com. Try our latest re-cycled challenge, #76, which is a corker of a question for testing your creative maths side! There are over 1,000 number challenges in total to try at this website.
Click this link if you wish to find out more about our maths workshops when visiting schools – the 7puzzle experience.
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Paul Godding, Director of the 7puzzle company
It is possible to use seven 4′s (4 4 4 4 4 4 4) once each, with the four operations + – x ÷, to make all the target numbers from 1-9.
For instance, to arrive at the number 1, you could do:
4 – (4÷4) – (4÷4) – (4÷4) = 1
Your task is to make each of the other target numbers 2-9 using seven 4′s. Can you make them all?
P.S. As an added bonus question for the real puzzle enthusiast, what is the LOWEST target number it is NOT possible to make using the seven 4′s?
Try the following calculations in your head to help improve your mental arithmetic. For the speedy number gymnasts, you have 10 seconds to get the correct answer to this 10-step question.
Start with the number 13, then:
-2 +5 ÷2 x5 -4 ÷9 +1 x5 -1 ÷4 = ?
Can you arrive at the target answer of 24 by using each of the digits 3, 3, 3 and 5 exactly once each, and with + – x ÷ available?
As well as 9+4+1, there are seven other ways of making 14 when adding together three unique digits from 1-9. Can you find these seven other combinations?
From the numbers 2-18, find the only one remaining when you eliminate all square numbers, multiples of 6, factors of 40 and odd numbers.
This number puzzle can be solved by repeated subtraction, but is there a quicker way of reaching the answer?
Start at 100 and keep on subtracting 7 until you hit a single-digit number. What is this number?
As when playing the possible game, use the numbers 1, 4 and 6 once each, with + – x ÷ available, to try and find which SIX target numbers it is mathematically possible to achieve, but this time within the range 20-30.
Full details of the possible game can be found at mathematicallypossible.com.
The playing board of the 7puzzle game contains 49 different numbers, ranging from 2 to 84. Keep this in mind when answering the following.
If you wrote down the first SEVEN prime numbers, plus all the multiples of 11 and factors of 24 that could possibly be on the playing board of the 7puzzle game, how many different numbers would be written on your list?
The playing board of the 7puzzle game contains 49 different numbers, ranging from 2 to 84.
If you wrote down all the multiples of 10, factors of 84 and square numbers that could possibly be on the playing board of the 7puzzle game, how many different numbers would be on your list?