Page:Methods of Operating the Comptometer (1895).djvu/30

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To reduce pounds, shillings and pence to United States Currency, at any given rate, multiply the pounds by 480. Leaving that on the register, multiply the shillings by 24 and the pence by 2; then multiply (by rule for high decimals on page 10) the result, by the number opposite the given rate of exchange in the table, page 27. Point off from the left of the machine two more holes than there are pounds in the bill of exchange, and the answer, expressed in dollars, cents and mills, is shown in the register.

Example: Find the value in dollars of £352 9s 7d at 4.8778.

After multiplying 352 by 480, and on top of that 9s by 24 and 7d by 2, 169190 appears on the register.

The number opposite the rate of exchange (4.8778) being 10164062, multiply 169190 by 10164062 from the left according to the rule for high decimals (page 10), and pointing off five holes from the left of the machine, 1719.656, the answer in dollars, cents and mills, appears on the register.

To reduce dollars and cents to English Currency at any given rate set the dollars and cents so that units of cents will come three columns from the right of the machine and turn down the third pointer and divide by the number in the table, opposite the given rate, until you have obtained the quotient figure one place to the right of the pointer. Subtract out the remainder. If the figure to the right of the pointer be less than five, subtract it out with the remainder; if more than 5, carry one to the left before subtracting it out.

Divide the quotient now standing in the register by 24, then turn down the fifth pointer from the right of the machine and divide the amount to the right of the fifth pointer by 2, and then divide the amount to the left of the fifth pointer by 20; turn down the seventh pointer and that to the left of the seventh pointer is pounds, that between the seventh and fifth pointers is shillings, that in the first column to the right of the fifth pointer is pence, and the figures to the left of that, half pence.

Note: If the remainder after dividing by 24 is over 19, you have to take the remainder off to divide it by 2. Of