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7. Reduce 1201. 10s. Massachusetts currency, into South Carolina and Georgia currency. Ans. £93 14s. 5 d.
8. Reduce 4101. 18s. 11d. Rhode-Island currency, into Canada and Nova-Scotia currency. Ans. £342 Is. Id. :
9. Reduce 5241. 8s. 4d. Virginia, &c. currency, into ster ling money.
Ans. £393 6s. 3d. 10. Reduce 2141. 9s. 2d. New-Jersey, &c. currency, inta N. Hamp. Massachusetts, &c.currency. Ans. 1711. 11s. 4d.
11. Reduce 1001. New-Jersey, &c. currency, into New York and North-Carolina currency. Ans. 1061. 13s. 4d.
12. Reduce 1001. Delaware and Maryland currency into sterling money.
Ans. 602. 13. Reduce 1161. 10s. New-York currency, into Connecticut currency.
Ans. 871. 7s. 6d. 14. Reduce 1121. 7s. 3d. S. Carolina and Georgia curren. cy, into Connecticut, &c. currency. Ans. 1441. 9s. 3;d.
15. Reduce 1001. Canada and Nova-Şcotia currency, inte Connecticut currency.
Ans. 1201. 16. Reduce 1161. 14s. 9:1. sterling money, into Connec ticut currency.
Ans. 1551. 13s. 17. Reduce 101. 10s. Canada and Nova-Scotia curren cy, into New-York currency.
Ans. 1671. 4s. 18. Reduce 1001. Nova-Scotia currency, into New-Jer sey, &c. currency.
RULE OF THREE DIRECT. THE Rule of Three Direct teaches, by having three numbers given to find a fourth, which shall have the same proportion to the third, as the second has to the first.
1. Observe that two of the given numbers in your ques. tion are always of the same name or kind; one of which must be the first number in stating, and the other the third number ; consequently the first and third numbers must al ways be of the same riame, or kind; and the other number, which is of the same kind with the answer, or thing sought, will always possess the second or middle place.
2. The third term is a demand ; and may be known by these or the like words before it, viz. What will ? What cost? How many? How far? How long? or, How much? &c.
* RULE.-1. State the question; that is, pl.ce the numbers so that the first and third terms may be of the sam3 kind; and the socond fierin of the same kind with the answer, or thing sought.
2. Bring the first and third terms to the same denomination, and reduce the second term to the lowest name mentioned in it. at 3. Multiply the second and third terms together, and divide their product by the first term; and the quotient will be the answer to the question, in the same denomination you left the second term in, which inay be brought into any other denomination required.
The method of proof is by inverting the question. (NOTE.-The following methods of operation, when they can be used, perform the work in a much shorter manner than the general rule.
1. Divide the second term by the first; multiply the quotient into the third, and the product will be the answer. Or,
2. Divide the third term by the first ; multiply the quotient into the second, and the product will be the answer. Or,
3. Divide the first term by the second, and the third by that quotient, and The last quotient will be the answer. Or,
4. Divide the first term by the third, and the second by that quotient, and the last quotient will be the answer.]
EXAMPLES. 1. If 6 yards of cloth cost 9 dollars, what will 20 yards cost at the same rate ?
Yds. % Yds. Here 20 yards, which moves the 6:9 : : 20 question, is the third term ; 6 yds.
9 the same kind, is the first, and 9 dollars the second.
Ans. $30 B. 2. If 20 yards cost 30 dols. 3. If 9 dollars will buy 6 what cost 6 yards ?
yards, how many yards will Yds. Yds. 30 dols. buy? $ yds. $ 20 : 30 : : 6
18. Bought 10 pieces of cloth, each piece containing 97 yards, al lls. 4 d. per yard; what did the whole come to 3
Ans. £55 9s. Ud.
FEDERAL MONEY. · Note 1. You must state the question, as taught in the Rules foregoing, and after reducing the first and third terms to the same name, &c. you may multiply and divide according to the rules in decimals; or by the rules for multiplying and dividing Federal Money.
EXAMPLES. 19. If 7 yds. of cloth cost 15 dollars 47 cents, what will 12 yds cost ?
Yds. $ cts. yds.
Ans. 26,52=$26, 52 cts. - But any sum in dollars and cents may be written down Ás a whole number, and expressed in its lowest denomination, as in the following example: (See Reduction of Federal Money, page, 62.)
20. What will 1 qr. 9 lb. sugar come to, at 6 dollars 45 Ots. per cwt. ? gr. lb. lb. cts. lb. 19 As 112 : 645 : : 37
NOTE 2. When the first and third numbers are federal money, you may annex ciphers, (if necessary,) until you make their decimal places or figures at the right hand of the separatrix, equal : which will reduce them to a like de. nomination. Then you may multiply and divide, as in whole numbers, and the quotient will express the answer in the least denomination mentioned in the second, or middle term.
EXAMPLES. 21. If 3 dols. will luy 7 yds. of cloth, how many yds.can ) buy for 120 dols. 75 cts.? cts. yds. cts.
As 300 : 7 :: : 12075
$ cts. 23. If a man lay out 121, 23 in merchandise, and thereby gaivs $39 51 cts. how much will he gain by laying out $12 at the same rate ? Cents. Cents. Cents.
As 12123 : 3951 :- : 1200
cts. $ cts. 12123)4741200(391=3,91 Ans. 36369