T he Main Challenge
Your starting number is 18 and your task is to arrive at the same final answer. There are ten arithmetical steps from beginning to end, each one involving a whole number, but the 9th (and penultimate) step is missing! What must it be?
÷2 +3 –8 ×6 +4 –3 ÷5 ×2 ? ×2 = 18
The 7puzzle Challenge
The playing board of the 7puzzle game is a 7-by-7 grid of 49 different numbers, ranging from 2 up to 84.
The 4th & 6th rows contain the following fourteen numbers:
3 5 10 12 18 20 32 33 35 44 49 54 56 60
What is the difference between the lowest and highest multiples of 4?
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 59 when using Lagrange’s Theorem. Can you find them?
The Mathematically Possible Challenge
Using 1, 6 and 7 once each, with + – × ÷ available, which FOUR numbers is it possible to make from the list below?
6 12 18 24 30 36 42 48 54 60
#6TimesTable
The Target Challenge
Can you arrive at 59 by inserting 4, 5, 6 and 10 into the gaps on each line?
- ◯×◯+◯–◯ = 59
- ◯²+◯×◯+◯ = 59
- (◯+◯)×◯–◯ = 59
Answers can be found here.
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