T he Main Challenge
Can you insert the numbers 0 to 9 exactly TWICE each into the gaps below so all five lines work out arithmetically?
◯ + ◯ = 15 = ◯ + ◯
◯ + ◯ = 5 = ◯ – ◯
◯ + ◯ = 10 = ◯ × ◯
◯ – ◯ = 2 = ◯ ÷ ◯
◯ + ◯ = 9 = ◯ × ◯
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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 3rd & 6th rows contain the following fourteen numbers:
5 12 13 18 20 25 33 36 42 45 49 56 66 80
What is the sum of the numbers in the 40’s?
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 131 when using Lagrange’s Theorem. Can you find them all?
The Mathematically Possible Challenge
Using 3, 6 and 10 once each, with + – × ÷ available, which SIX 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 131 by inserting 4, 5, 7 and 9 into the gaps on each line?
- ◯×◯×◯–◯ = 131
- ◯×◯×√◯+◯ = 131
Answers can be found here.
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