The Main Challenge
From the numbers 1-30 inclusive, delete:
- multiples of 5
- factors of 36
- numbers containing a ‘7’
- prime numbers
- even numbers
Which is the only number that remains?
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 & 7th rows contain the following fourteen numbers:
2 4 9 11 14 15 22 24 27 30 40 70 72 77
Which three different numbers on the list have a sum of 100?
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 SIX ways of making 123 when using Lagrange’s Theorem. Can you find them?
The Mathematically Possible Challenge
Using 2, 4 and 12 once each, with + – × ÷ available, which THREE numbers is it possible to make from the list below?
12 24 36 48 60 72 84 96 108 120
#12TimesTable
The Target Challenge
Can you arrive at 123 by inserting 3, 9, 10 and 12 into the gaps on each line?
- ◯×◯+◯÷◯ = 123
- ◯×◯+half(◯×◯) = 123
- (◯+◯)×◯+half◯ = 123
Answers can be found here.
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