21. If 3 dollars will buy 7 yards of cloth, how many yards can I buy for 120 dollars, 75 cents ? cts. yds. cts. As 300 : 7 :: 12075 7 yds. 300)84525(281 Ans. 22. If 12 lb. of Tea cost 6 dols. 600 18 cts. and 9 mills, what will 5lb. cost at the same rate? 2452 2400 525 300 Scts.in. 225 900(3qrs. 900 $ cts. 23. If a man lays out 121, 23 in mercbandize, ana thereby gains, 39 dollars, 51 cts. how much will he gain by laying out 12 dollars at the same rate ? Cents. Cents. Cents. 1200 -cts. $ cts. 12123)4741200(391–3,91 Ans. 36369 110430 13230 1107 24. If the wages of 15 weeks come to 64 dolš. 19 cts. what is a year's wages at that rate? Ans. $222, 52 cts. 5m. 25. A man bought sheep at 1 dol. 11 cts. per head, to the amount of 51 dols. 6 cts. ; how many sheep did he buy? Ans. 46. 26, Bought 4 pieces of cloth, each piece containing 31 yards, at 16s. 6d. per yard, (New-England currency) what does the whole amount to in Federal Money? Ans. $341. 27. When a ton of wine cost 140 dollars, what cost a quart? Ans. 13cts. 88 m. 28. A merchant agreed with his debtor, that if he would pay him down 65 cents on a dollar, he would give him up a note of hand of 249 dollars, 88 cts. I demand what the debtor must pay for his note ? Ans. $162 42cts. 2m. 29. If 12 horses eat up 30 bushels of oats in a week, how many bushels will serve 45 horses the same time ? Ans. 1121 bushels. 30. Bought a piece of cloth for $48 27cts. at 1 dollar 19 cents per yard ; how many yards did it contain ? Ans. 40yds. 2 qrs. 31. Bought 3 hhds. of sugar, each weighing 8 cwt. lqr. 12 lb. at 7 dollars, 26 centi per cut. what come they to ? Ans. $182 Ict. 8m. 32. What is the price of 4 pieces of cloth, the first piece containing 21, the second 23, the third 24, and the fourth 27 yards at 1 dollar 43 cents a yard ? Ans. $135 85cls. 21+23+24+27=95yds. 33. Bought 3 hhds. of brandy, containing 61, 62, 624 gallons at 1 dollar 38 cts. per gallon, I demand how much they amount to ? Ans. $255 99cts. 34. Suppose a gentleman's income is 1836 dollars a year, and he spends 3 dollars 49 cents å day, one day with another, how much will he have saved at the year's end ? Ans. $562, 15cls. 35. If my horse stand me in 20 cts per day keeping, what will be the charge of 11 horses for the year at that rate? Ans. $803. 36. A merchant bought 14 pipes of wine, and is allow ed 6 months credit, but for ready money gets it 8 cent a gallon cheaper; how much did he save by paying ready money? Ans. $141, 12 centsa EXAMPLES-Promiscuously placed. 37. Sold a ship for 5371. and I owned 'f of her ; what was my part of the money? Ans. £201 7s. 6d. 38. If it of a ship cost 781 dollars 25 cents, what is the whole worth ? As 5 : 781,25 : : 16 : 2500 Ans. 39. If I buy 54 yards of cloth for £31 103. what did It cost per Ell English? Ans. 14s. 7d. 40. Bought of Mr. Grocer, 11 cwt. 3 qrs. of sugar, at S dollars 12 cents per cwt. and gave him James Paywell's note for 191. 7s. (New England currency) the rest I pay in čash; tell me how many dollars will make up the balance ? Ans. $30, 91 cls. 41. If a staff 5 feet long casts a shade on level ground 8 feet, what is the height of that steeple whose sbade at the same time measures 181 feet? Ans. 113} ft. 42. If a gentleman has an income of 300 English guineas a year, how much may he spend, one day with another, to lay up 500 dollars at the year's end? Ans. 82, 46cts. 5m. 43. Bought 50 pieces of kerseys, each 34 Ells Flemish, at 85. 4d. per Ell-English ; what did the whole cost ? Ans. £425, 44. Bought 200 yards of cambrick for 90l, but being damaged, I am willing to lose 71. 193. by the sale of it; 1 hat must I demand per Ell-English? Ans. 10s. 3 d. 45. How many pieces of Holland, each 20 Ells-Flem. ish, may I have for 231. 8s. at 6s. 6d. per Ell-English 3 Ans. 6pieces. 46. A merchant bought a bale of cloth containing 240 yards, at the rate of dollars for 5 yards, and sold it again at the rate of 114 dollars for 7 yards ; did he gain or lose by the bargain, and how much? Ans He gained $25,71cts. Im. + 47. Bought a pipe of wine for 84 dollars, and found it had leaked out 12 gallons ; I sold the remainder at 12 cents a pint; what did i gain or lose? Ans. I gained $30. 48. A gentleman bought 18 pipes of wine at 12s. 6d. (New Jersey currency) per gallon; how many dollars will pay the purchase ? Ans. $3780. 49. Bought a quantity of plate, weighing 15lb. lloz. 13pwt. 17gr. how many dollars will pay for it, at the rate of 12s. 7d. New-York currency, per ounce. Ans. $301,50cls. 2, m. 50. A factor bought a certain quantity of broadcloth and drugget, which together cost 81l: the quantity of broadcloth was 50 yards, at 18s, per yard, and Icr erery 5 yards of broadcloth he had 9 yards of drugget; I demand how many yards of drugget he had, and what it cost him per yard ? Ans. 90 yards at Ss. per yard. 51. If I give 1 eagle, 2 dollars, 8 dimes, 2 cents and 5 mills, for 675 tops, how many tops will 19 mills buy? Ans. 1 top. 52. Whereas an eagle and a cent, just three score yards did buy, How many yards of that same cloth for 15 dimes had I ? Ans. Syds. 3qrs. 3na. + 53. If the Legislature of a State grant a tax of 8 mills on the dollar, how much must that man pay who is 319 dollars, 75 cents on the list ? Ans. $2,55cts. 3m. 54. If 100 dcllars gain 6 dollars interest in a year, how much will 49 dollars gain in the same time ? Ans. $2,94cts. 55. If 60 gallons of water, in one hour, fall into a cistern containing 300 gallons, and by a pipe in the ciso tern, 35 gailons run out in an hour ; in what time will it be filled ? Ans. in 12 hours. 58. A and B depart from the same place and travel the same road; but A goes 5 days before B, at the rate of 15 miles a day; B follows at the rate of 20 miles a day; what distance must he travel to overtake As Ans. 300miles the RULE OF THREE INVERSE. The HE Rule of Three Inverse, teaches by having three numbers given to find a fourth, which shall have the same proportion to the second, as the first has to the third. If more requires more, or less requires less, question belongs to the Rule of Three Direct. But if more requires less, or less requires more, the question belongs to the Rule of Three Inverse; which may alivays be known from the nature and tenor of the question. For Example : If 2 men can mow a field in 4 days, how many day will it require 4 men to mow it? days 1. If 2 require 4 how much time will 4 require Answer, 2 days. Here more requires less, viz. the more men the less time is required. days 2. If 4 require 2 how much time will 2 require ? Answer, 4 days. Here less requires more, viz, the less the number of men are, the more days are required~ therefore the question belongs to Inverse proportion. meni men men RULE. 1. State and reduce the terms as in the Rule of Three Direct. 2. Multiply the first and second terms together, and divide the product by the third ; the quotient will be the answer in the same denomination as the middle term was reduced into. EXAMPLES. 1. If 12 men can build a wall in 20 days, how many men can do the same in 8 days ? Ans. 30 mnen. 2. If a man performs a journey in 5 days, when the day is 12 hours long, in how many days will he perform it when the day is but 10 hours long? Ans. 6 days. 3. What length of board, 7) inches wide, will make a Ans. 19 inches. square foot. |