The Main Challenge
In this particular number puzzle, three UNIQUE digits from 1-9 must be used to arrive at a specified target number; today is 42.
The formula is always the same; multiply two numbers together, then either add or subtract a third number to achieve your target.
One way to make 42 is (9×4)+6; can you find the only other TWO ways of making 42?
[Note: (9×4)+6 and (4×9)+6 counts as just ONE way.]
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 columns contain the following fourteen numbers:
7 8 11 14 18 25 30 36 40 44 49 54 64 84
What is the difference between the highest and lowest multiples of 4?
The Factors Challenge
Which SIX numbers below are factors of 320?
2 4 6 8 10 12 14 16 18 20
The Mathematically Possible Challenge
Using 4, 7 and 11 once each, with + – × ÷ available, which is the ONLY number it is possible to make from the list below?
100 101 102 103 104 105 106 107 108 109
#Numbers100to109
The Target Challenge
Can you arrive at 320 by inserting 10, 20, 30, 40 and 50 into the gaps on each line below?
- ◯×◯×(◯–◯)÷◯ = 320
- (◯+◯)×◯÷(◯–◯) = 320
- (◯–◯–◯÷◯)×◯ = 320
Answers can be found here.
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