Delisser's Interest and Average Tables, seven per cent, a new method, combining accuracy, speed, and simplicity, by which the interest on any amount, from $1 to $3,600, for any period, from one day to one year, “can be found at a glance,” and for averaging even the most intricate accounts in a shorter time, and with fewer figures, than by any other system


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The Tutor's Assistant


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The Encyclopædia Britannica


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