As usual with these tube puzzles, each number should be used once, and once only, and must be added, subtracted, multiplied or divided to make a balanced equation.
What makes this special is that there are at least three perfect solutions, ie solutions that use the numbers in the order they appear.
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My solutions: 9 - 1 ( ÷ 2) = 7 - 3
9 - 1 + 2 = 7 + 3
9 - 1 + 2 - 7 = 3
If there's a solution just using + and - there's always going to be at least 4 solutions, just by putting the = in all possible positions.
ReplyDelete9 - 1 + 2 = 7 + 3
9 - 1 + 2 - 7 = 3
9 - 1 = - 2 + 7 + 3
9 = 1 - 2 + 7 + 3
Well, maybe, but starting half an equation with a minus is a bit dodgy
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