Th e Main Challenge
All of the following 3-digit numbers are divisible by 3, but only one is also a multiple of 9. Which one?
237 276 303 336 495 528 582 660 744 771 888 939
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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 5th & 6th rows contain the following fourteen numbers:
5 6 7 12 16 18 20 21 33 49 50 56 81 84
What is the difference between the highest and lowest multiples of 7?
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 FOUR ways of making 116 when using Lagrange’s Theorem. Can you find them?
The Mathematically Possible Challenge
Using 2, 4 and 12 once each, with + – × ÷ available, which TWO numbers are NOT possible to make from the list below?
4 8 12 16 20 24 28 32 36 40
#4TimesTable
The Target Challenge
Can you arrive at 116 by inserting 2, 3, 4 and 9 into the gaps on each line?
- (◯×◯+◯)×◯ = 116
- ◯³+◯²+◯²–◯³ = 116
- ◯³×◯–(◯+◯) = 116
Answers can be found here.
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