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Place 5 opposite 1: now 1 is opposite 2, the

answer.

TO MULTIPLY ONE FRACTION BY ANOTHER.

RULE. Reduce one to decimals: then place the numerator of the other opposite the denominator: then opposite the decimal is the answer in decimals, which, if desired, can be reduced to a vulgar fraction by the preceding rules.

TO REDUCE THE DIFFERENT CURRENCIES TO FEDERAL MONEY.

RULE. Place the 1 on the circular, opposite the number of shillings and parts of a shilling composing a dollar of the currency to be reduced: then, opposite the given number of shillings is the answer.

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Example.-Reduce 5 shillings, New York currency, to Federal money.

Place 1 (on the circular) opposite 8: then opposite 5 shillings, is 625, the answer.

In 15 shillings, how much?

Opposite 15 is 1.875, the answer.

In 32 shillings, English currency, how much? Place 1 (on the circular) opposite 45: then opposite 32, is $7.11, the answer.

In 9 shillings, how much?
Opposite 9 is $2, the answer.

INTEREST.

TO COMPUTE INTEREST FOR YEARS.

RULE. Place the rate per cent. found on the cir cular, opposite 1: then opposite the principal is the interest.

·Example. What is the interest of $50 at 7 per cent.?

Place 7 opposite 1: then opposite 50 is $3.50, the

answer.

What is the interest on $40 at 6 per cent.? Place 6.5 opposite 1: then opposite 40 is $2.60, the answer.

TO COMPUTE INTEREST FOR MONTHS.

RULE. Place the principal, (found on the circular,) opposite the gauge point for months at the given per cent. then opposite the given number of months is the answer.

Example.-What is the interest on $50 for three months at 7 per cent.?

Place 50, (found on the circular,) opposite 1714, (the gauge point for months at 7 per cent.,) then opposite 3 months is 875, the answer.

What is the interest on $60. for eight months at 6 per cent ?

Place 60 opposite 2, (the gauge point for months at 6 per cent.,) then opposite 8 months is $2.40, the

answer.

TO COMPUTE INTEREST FOR DAYS.

RULE.-Place the principal, (found on the circular,) opposite the gauge point for days at the given per cent. then opposite the number of days is the answer. Example.-What is the interest on $55 for 15 days at 6 per cent?

Place 55 opposite ·600, (the gauge point for days at 6 per cent.,) then opposite 15 days is ·13 3-4.

THE PRINCIPAL AND INTEREST BEING GIVEN, TO FIND

THE RATE PER CENT.

RULE FOR ONE YEAR.-Place the interest opposite the principal: then opposite 1 is the rate per cent. Example.-Received $7.00 for the use of $50.00 for one year; what was the rate per cent.?

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Place 7 opposite 50: then opposite 1 is 14, the answer, 14 per cent.

Gave $4.00 for the use of $80.00 one year: whatwas the rate per cent. ?

Place 4 opposite 80: then opposite 1 is 5, the answer, 5 per cent.

RULE FOR MONTHS.-Place the given interest opposite the given number of months: then observe the number opposite 12. Now place this number opposite the principal: then opposite 1 is the rate per

cent.

Example.-Paid 25 cents for the use of $5.00 for 4 months: what was the rate per cent.?

Place 25 opposite 4: then opposite 12 is 75. Now place 75 opposite $5.00: then opposite 1 is 15, (15 per cent.,) the answer.

Gave 14 cents for the use of $60.00 one month : what was the per cent.?

Place 14 opposite 1: then opposite 12 is 1.68Now place 1.68 opposite 60: then opposite 1 is 2.8, (2 per cent.,) the answer.

RULE FOR DAYS.-Place the given interest opposite the given number of days: then observe the interest opposite 365 (the number of days in a year). Place this opposite the principal: then opposite 1 is the rate per cent.

Example.-Paid 14 cents for the use of $64.00 29 days: what was the rate per cent.?

Place 14 opposite 29: now opposite 365 is $1.76. Now place 1.76 opposite 64: then opposite 1 is 2-75, (2 per cent.,) the answer.

Paid 23 cents for the use of $50.00, 21 days: what was the rate per cent. ?

Place 23 opposite 21: now opposite 365 is 4. Place 4 opposite 50: then opposite 1 is 8 per cent., the answer.

THE RATE PER CENT. AND THE INTEREST BEING GIVEN, TO FIND THE PRINCIPAL.

RULE FOR ONE YEAR.-Place the per cent. opposite 1 then opposite the interest is the principal. Example.-At 7 per cent. I paid $3.50 for the use of money 1 year: what was the principal?

Place 7 opposite 1: then opposite 3.50 is $50-00, the answer.

RULE FOR MONTHS.-Place the interest opposite the given number of months: then opposite the point of the given per cent., for months, is the answer.

Example.-Gave $2.00 at 7 per cent. for three months what was the principal?

Place 2 opposite 3: then opposite 1-714 is $114-30, the answer.

RULE FOR DAYS.-Place the given interest opposite the given number of days: then opposite the gauge point for days stands the principal.

Example.-At 7 per cent., gave 15 cents for 20 days: what was the principal?

Place 15 opposite 20: then opposite 521 (the gauge point for days at 7 per cent.) is $39.00, the

answer.

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