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So, it's time to take a look at operator crossword puzzles.
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This is an operator crossword puzzle and
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it's a puzzle where there are digits inside or numbers inside
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and the numbers, when an operator is placed between any two numbers or any row
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gives the result written outside the rows and outside the columns
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so all we need to do is fill in the missing squares, the blanks
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with operators. In this simple operator crossword, you need to just
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plug in plus, minus, multiplication and division and try and
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get the numbers in the rows and in the columns and
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by the way, this operator crossword doesn't have a unique solution, there can be many solutions, you can see this already in the top row
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- to get 18 you can either multiply 9 by 6 to get, six nines are 54
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and divide that by 3 to get 18,
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or you can just write two plusses here, 9 plus 6 is 15, plus 3 is 18.
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So, we've done the first row. The second row - 5 something 2 something 4 gives minus 1
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and this is also pretty easy: five minus 2 is 3 minus 4 is minus 1.
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And we need to get 2 from 1, 8 and 7
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so 1 plus 8 is 9, minus 7 gives us 2.
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You have to make sure by the way that the operators operate in order.
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Multiplication and division before addition and subtraction.
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So, let's try now with the columns and get from 9,5 and 1, 13, and again this is pretty simple -
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9+5 is 14, -1 is 13.
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and in the middle, 6,2 and 8 we need to find an operation that gives us 11,
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notice that here, all the numbers are even, so we're going to somehow need to get
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from two odd numbers an even number
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so that the sum will be, Err.. from two even numbers an odd number, so that the sum will be odd
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and the way to do this is by division. That's the only way, by the way, you can do this if you're given
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just even numbers, so, 6 divided by 2 is 3,
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and 3 plus 8 is 11, and the last one, 3,4 and 7 have to give us 5,
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and this can be done in the following way: three fours are twelve, minus seven is five.