T he Main Challenge
How can you use six 7’s (7 7 7 7 7 and 7) once each, together with the four arithmetical operations + – × ÷, to arrive at the target answer of 100?
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 4th & 5th rows contain the following fourteen numbers:
3 6 7 10 16 21 32 35 44 50 54 60 81 84
What is the sum when adding together all the multiples of 10?
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 FIVE ways of making 86 when using Lagrange’s Theorem. Can you find them?
The Mathematically Possible Challenge
Using 2, 3 and 11 once each, with + – × ÷ available, which THREE numbers is it possible to make from the list below?
11 22 33 44 55 66 77 88 99 110
#11TimesTable
The Target Challenge
Can you arrive at 86 by inserting 2, 4, 10 and 14 into the gaps on each line?
- ◯×(◯–◯)+◯ = 86
- ◯×◯÷◯+◯² = 86
- (◯²–◯)÷◯–◯ = 86
Answers can be found here.
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