Sect. I.

Problem VIII.

Betwixt Two Numbers given, to find a Mean Geometrically Proportional.

Set one of the Numbers given upon C, to the same Number upon D, and then against the other given Number upon C, is the Geometrical Mean sought.

    Example. Let the Numbers given be 50 and 72, to find a Geometrical Mean, &c.

    Set 50 upon C, to 50 upon D, and then against 72 upon C, is 60 upon D. So 60 is a Geometrical Mean betwixt 50 and 72. Or thus:

    Set 72 upon C, to 72 upon D, and then against 50 upon C, is 60 upon D, the Mean as before.

By the Pen thus:

    Multiply one Number by the other, then extract the Square-Root of the Product, this Square-Root is the Geometrical mean between the two Numbers given; thus 72 multiplied by 50, is 36000, whose Square-Root is 60, the Geometrical Mean betweebn 50 and 72.

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This page was last updated on 29 March 2000.