T he Main Challenge
The 15 arithmetical steps below include percentage & fraction calculations as well as big additions & multiplications:
Start with the number 28, then:
- subtract seventy-five percent
- +69
- –4
- 1/2 of this
- square root of this
- ×15
- multiply by one
- +80%
- –10
- add four hundred and sixty-five
- subtract three hundred and seventeen
- two-thirds of this
- ×0.5
- increase by 10%
- decrease by 10%
What is your final answer?
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
Which of these numbers, when 65 is added to it, becomes a square number?
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 SEVEN ways of making 132 when using Lagrange’s Theorem. Can you find them all?
The Mathematically Possible Challenge
Using 3, 6 and 10 once each, with + – × ÷ available, which FOUR numbers is it possible to make from the list below?
7 14 21 28 35 42 49 56 63 70
#7TimesTable
The Target Challenge
Can you arrive at 132 by inserting 4, 5, 6 and 8 into the gaps on each line?
- (◯+◯)×(◯+◯) = 132
- (◯×◯–double◯)×◯ = 132
Answers can be found here.
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