Th e Main Challenge
Carry out the following 15-step number trail – with no calculator!
Start with 20, then:
+1 ÷3 ×5 –7 +2 ÷6 +4 –1 ×3 ÷4 +4 –5 ×1 +3 ×6 = ?
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 2nd & 3rd rows contain the following fourteen numbers:
8 13 17 25 28 36 42 45 48 55 63 64 66 80
Which three different numbers 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 81 when using Lagrange’s Theorem. Can you find them all?
The Mathematically Possible Challenge
Using 2, 3 and 11 once each, with + – × ÷ available, which TWO numbers are 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 81 by inserting 2, 3, 6 and 9 into the gaps on each line?
- ◯×◯×◯÷◯ = 81
- ◯²×◯×◯÷◯ = 81
- ◯²+◯×(◯+◯) = 81
Answers can be found here.
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