Your task is to multiply two numbers together and then subtract a third number to achieve the target answer of 7. The three numbers used in each calculation must all be unique digits from 1-9.
For example, one such way of making 7 is by doing (4×3)–5, so can you find the other SIX ways you can make 7?
[Note: (4×3)–5=7 and (3×4)–5=7 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 rows of the playing board contain the following fourteen numbers:
5 6 7 12 16 18 20 21 33 49 50 56 81 84
Subtract the total of the prime numbers from the sum of the multiples of 10. What answer do you get?
. . . can be found when clicking this.