Mathematical table

Before calculators were cheap and plentiful, people would use mathematical tables —lists of numbers showing the results of calculation with varying arguments— to simplify and drastically speed up computation. Most common are tables of multiplication, which most people know from their early math classes:

Related Topics:
Calculator - Computation - Multiplication

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×123456789101112

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1 123456789101112

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2 .....4681012141618202224

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3 ..........9121518212427303336

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4 ...............162024283236404448

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5 ....................2530354045505560

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6 .........................36424854606672

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7 ..............................495663707784

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8 ...................................6472808896

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9 ........................................819099108

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10 .............................................100110120

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11 ..................................................121132

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12 .......................................................144

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To find 7×8, you'd look in the left column to seven, then across the "seven-line" to eight. The easily found answer is 56. To find 9×3, you'd swap the factors and find the equal product 3×9 (27) by the same technique.

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