The Main Challenge
Divide these nine numbers into three groups of three so that the sum of each group is the same:
11 25 35 43 51 63 73 85 91
What is this sum?
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 & 3rd rows of the playing board contain the following fourteen numbers:
2 9 13 14 15 22 25 36 40 42 45 66 72 80
What is the difference between the 2nd highest even number and 2nd lowest odd number?
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 SEVEN different ways to make 204 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 THREE numbers 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 204 by inserting 1, 4, 5 and 10 into the gaps on each line?
- (◯+◯×◯)×◯ = 204
- double(◯²+◯+◯–◯) = 204
- (◯³–treble◯)×(◯+◯) = 204
Answers can be found here.
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