37148

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+2+2 then -3 you get £1 with that it proves you can make an infinite number of changes as you can change you bank account by any number if you wanted 2, 3, 4 or 1000 pound you could make it as if you can make one all you need to do is ((2+2-3)*x)= any number
even with 3 and 7 if you use ((3*5)-(7*2))=£1 so ((3*5)-(7*2))*x is virtually any number
so the key is one number has to be larger than the other so if x remains smaller than y then virtually any number is possible