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We can arrange short sticks to make grid of squares, as in the 3 x 3 example of the figure below, which requires 24 sticks. How many sticks are required to make a 151 x 143 grid of squares?

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    $\begingroup$ I'm voting to close this because it appears to be a puzzle found elsewhere and also just a mathematical problem (rather than a mathematical puzzle) $\endgroup$
    – melfnt
    Nov 26 '20 at 15:15
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    $\begingroup$ "of the figure below" - which figure? I think you forgot to include it. $\endgroup$ Nov 26 '20 at 15:33
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Each "point" has 2 attached sticks. Except last (or first) row and last (or first) column which has one more.
So I think it would be

151 * 143 * 2 + 151 + 143 = 43480

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    $\begingroup$ Please don't answer blatantly off-topic questions $\endgroup$
    – bobble
    Nov 26 '20 at 16:13
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A (R x C) grid of squares made from sticks has (C+1) columns of sticks and (R+1) rows of sticks.

Each row has C sticks. Each column has R sticks.

Vertical sticks (columns) = (C+1)(R) = RC+R Horizontal sticks (rows) = (R+1)(C) = RC+C

Total = 2RC + R + C


Math check:

1x1 = 2 + 1 + 1 = 4

1x2 = 4 + 1 + 2 = 7

3x3 = 18 + 3 + 3 = 24

151x143 = 2(151x143)+151+143 = 43480

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    $\begingroup$ Please don't answer blatantly off-topic questions $\endgroup$
    – bobble
    Nov 26 '20 at 16:13

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