The Main Challenge
Using the three numbers 3, 6 and 9 just once each, with + – × ÷ available, THREE of the following target numbers are not possible to make:
3 6 9 12 15 18 21 24 27 30 33 36
What is the sum of these three impossible numbers?
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 & 7th rows contain the following fourteen numbers:
4 6 7 11 16 21 24 27 30 50 70 77 81 84
Which number on the list, when multiplied by 5, has its result also on the list?
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 THREE ways of making 33 when using Lagrange’s Theorem. Can you find them?
The Mathematically Possible Challenge
Using 2, 6 and 11 once each, with + – × ÷ available, which is the ONLY number 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 33 by inserting 2, 3, 4 and 5 into the gaps on each line?
- (◯+◯+◯)×◯ = 33
- (◯+◯)×◯–◯ = 33
- (◯³+◯–◯)÷◯ = 33
Answers can be found here.
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