The Main Challenge
Using seven 7’s (7 7 7 7 7 7 and 7) once each, with + – × ÷ available, it is possible to make various target answers, such as 7 as shown here:
- 7+7+7+7–7–7–7 = 7, or perhaps
- 7×(7÷7)×(7÷7)×(7÷7) = 7
In a similar way, show how to make the target answers 1, 2 and 3.
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 & 4th rows contain the following fourteen numbers:
3 10 13 25 32 35 36 42 44 45 54 60 66 80
What is the sum of the multiples of 4?
The Roll3Dice Challenge
From six of the seven groups of numbers below, it is possible to make today’s target number of 10 when each number in the group is used once and + – × ÷ is available:
- 1 1 6
- 1 2 6
- 1 5 5
- 2 2 3
- 2 4 5
- 3 5 5
- 4 5 6
Which is the only group that CANNOT make 10?
The Mathematically Possible Challenge
Using 4, 5 and 10 once each, with + – × ÷ available, which are the only TWO numbers it is 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 10 by inserting 2, 2, 3 and 5 into the gaps on each line?
- (◯–◯)×◯×◯ = 10
- (◯–◯÷◯)×◯ = 10
- (◯²–◯–◯)÷◯ = 10
- ◯÷(◯–◯÷◯) = 10
Answers can be found here.
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