MathemaGrids (BrainBashers)
Place the digits 1 to 9 so three across sums and three down sums all come out right.
Every day: Three new MathemaGrids every day (Puzzles A, B and C), each available with 0 to 3 starting hints, dated and the same for every visitor. New puzzle: Midnight GMT (the site lets you set your own time zone).
MathemaGrids on BrainBashers is a small arithmetic grid. You place each of the numbers 1 to 9 once in a 3x3 grid woven with +, -, x and ÷ signs, so that the three rows and three columns each work out to their totals, calculated strictly left to right and top to bottom.
About MathemaGrids (BrainBashers)
MathemaGrids is a cross-sum puzzle using all nine digits. The board is a 3x3 grid of empty squares with an operator between each pair, making three sums across and three sums down, each with its answer at the end. You place 1 to 9, each exactly once, so that all six sums are correct.
The twist is the order of operations: there isn't one. Every sum is worked strictly from left to right, or top to bottom, so 2 + 5 x 9 means (2 + 5) x 9 = 63, not 47. The site adds some helpful guarantees: you will never see ÷ 1 or x 1 (though 1 x can appear), and no step of a calculation ever drops below zero or turns into a fraction.
Kevin Stone's BrainBashers posts three of these a day, Puzzles A, B and C, all of a similar difficulty. Each can be opened with 0, 1, 2 or 3 random digits already placed as hints, and the play page also has a hint button, plus check, answer, print and restart, an option to show mistakes and an optional clock. The puzzles change at midnight GMT or at the time zone you set, and a few weeks of earlier days stay in the date list. No adverts, no account.
It suits anyone who enjoys mental arithmetic and wants a short daily number puzzle.
How to play MathemaGrids (BrainBashers)
- Open the Daily MathemaGrids page and choose Puzzle A, B or C, with 0 to 3 starting hints.
- Place each of the numbers 1 to 9 once in the nine empty squares.
- Work each row from left to right and each column from top to bottom, ignoring the usual order of operations.
- Make all three across sums and all three down sums equal their totals.
- Use the hint button if stuck, then check; three new grids arrive after midnight GMT.
Tips
- Start with sums that involve division: only a few pairs divide evenly.
- Large totals with two multiplications usually need the big digits 7, 8 and 9.
- Because no step goes below zero, a subtraction near the start limits which digit can come first.
- If you are new to it, open a puzzle with 2 or 3 hints and work down to 0.
Questions
Does multiplication come before addition?
No. Every sum is worked strictly left to right or top to bottom, so 2 + 5 x 9 is 63.
Can a calculation go negative or give a fraction?
No. The site says no step goes below zero or becomes fractional.
How many puzzles are there a day?
Three, Puzzles A, B and C, each available with 0 to 3 starting hints.
Is it free?
Yes, with no adverts and no account.
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