T he Main Challenge
This is very famous in Japan, having been an integral part of a TV advert for Google’s Nexus 7 tablet a few years ago. Click this YouTube link for a browse.
Using the numbers 1, 1, 5 and 8 exactly once each, with + – × and ÷ available, can you beat this tricky Japanese challenge by arriving at the target answer of 10?
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 of the playing board contain the following fourteen numbers:
6 7 8 16 17 21 28 48 50 55 63 64 81 84
How many more square numbers than prime numbers are listed above?
The Lagrange Challenge
Lagrange’s Four-Square Theorem states that every positive integer can be made by adding up to four square numbers.
For example, 7 can be made by 2²+1²+1²+1² (or 4+1+1+1).
There are NINE different ways to make 209 when using Lagrange’s Theorem. How many can you find?
The Mathematically Possible Challenge
Using 5, 7 and 11 once each, with + – × ÷ available, which are the only TWO numbers 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 209 by inserting 2, 7, 9 and 12 into the gaps on each line?
- ◯×◯×◯–◯ = 209
- (◯+◯)×(◯+◯) = 209
Answers can be found here.
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