The Main Challenge
Start with the number 13, then follow these ten arithmetic steps:
–2 +5 ÷2 ×5 –4 ÷9 +1 ×5 –1 ÷4 = ?
What is your final answer?
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 1st & 6th rows contain the following fourteen numbers:
2 5 9 12 14 15 18 20 22 33 40 49 56 72
Which four different numbers, when added together, have a total 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 FIVE ways of making 75 when using Lagrange’s Theorem. Can you find them?
The Mathematically Possible Challenge
Using 4, 6 and 12 once each, with + – × ÷ available, which TWO numbers is it possible to make from the list below?
1 4 9 16 25 36 49 64 81 100
#SquareNumbers
The Target Challenge
Can you arrive at 75 by inserting 3, 4, 5 and 10 into the gaps on each line?
- (◯+◯)×◯+◯ = 75
- ◯²×(◯–◯–◯) = 75
- ◯×◯+◯²+◯² = 75
Answers can be found here.
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