145. A's stock was in trade 12 months, B's 15 months, -and C's 18 months. A's gain was $600, B's 600, and C's $900; the whole stock was $7000; what was each man's share ? Ans. A, $2500; B, $2000; C, $2500. 146. A merchant commenced business with $20000; for three successive years he gained 20%, which was added to the capital of the previous year; what had he then ? Ans. $34560. 147. The standard of silver in the United States is o pure, and that of England 23% purer; what is the standard of England ? Ans. 17 148. 2 is what per cent of 4 ? Ans. 50%. 149. 12 is what per cent of 6 ? Ans. 200%. 150. 15 is what per cent of 50 ? Ans. 30%. 151. If A's money is 60% more than B's, how many per cent less than A’s is B’s ? Ans. 371%. 152. Standard gold and silver in the United States is 9 parts pure and 1 part alloy; what per cent is alloy ? Ans. 10%. 153. 25% of an article is how many per cent of of it? Añs. 30%. 154. If I sell of an article for what the whole cost, what per cent do I gain ? Ans. 25%. 155. If I sell of an article for what cost me, what per cent do I lose ? Ans. 113%. 156. The premium on a draft at 21% was $25; what was the face of the draft ? Ans. $1000. 157. At what rate per cent simple interest will a sum of money double itself in 5, 6, 8 and 9 years respectively ? Ans. 20%, 165%, 123% and 113%. 158. My annual interest at 6% is $3000 ; what is my principal ? Ans. $50000. 159. In what time will a sum of money double itself, simple interest at 5%? 6%? 8% ? and 10% respectively? Ans. 20, 164, 123 and 10 years. 160. What is the rate of interest when $120 is paid for the use of $600 for 3 years and 4 months simple interest ? Ans. 6%. 161. What principal at 6% simple interest will amount to $6900 in 2 years and 6 months ? Ans. $6000. 162. In what time will a sum of money treble itself at 5%? 6%? 8%? 10%, simple interest ? Ans. 40, 331, 25, 20 years. . 163. A steamboat whose rate is 12 miles an hour sails up a river whose current is 4 miles an hour, returning in 15 hours; how far up the river did the boat go ? Ans. 80 miles. 164. A and B engaged a piece of work. A can do it A in 8 days, and 3 in 12 days; how long will it take them both to do it? Ans. 4 days. 165. A can do a piece of work in day, B in f and in day; how long will it take them all working together to do it ? Ans. } day. 166. A tank has two pipes for supply and one for discharge; the first alone will fill it in 9 hours and the second in 12 hours, and the third will discharge it in 8 hours; in what time will the tank be filled with all the pipes in operation ? Ans. 14 hours. 167. A boy driving geese to market, sold to his first customer one-half of what he had and one-half a goose more: to the second and third customer he sold in like manner, without killing a goose, when he had none left ; how many had he at first ? Ans. 7 geese. 168. What is the cost of excavating a ditch 1 mile long, 6 feet wide, and 3 feet deep, at 40 cents per cubic yard ? Ans. $1408. 169. A rectangular lot of land is 80 rods in length 40 rods in width ; how many acres does it contain ? Ans. 20 acres. 170. A triangular lot has one side 40 rods long, and a perpendicular line from the opposite corner of the lot to this side 16 rods; how much land does it contain ? Ans. 2 acres. 171. A house valued at $15000, and furniture $3000, is insured for of its value at 11%; what is the premium? Ans. $180. 172. What per cent on the value of a house, is a premium of $24 on $960, which is the value of the house? Ans. 19% 173. The principal is $900, the time 2 yr. 4 mo. 20 dan, 4 and the interest $150.50; what is the per cent ? Ans. 7%. 174. The principal is $1350, the interest $225.75, the rate 7%; what is the time? Ans. 2 yr. 4 mo. 20 da. 175. Paid $850 in currency for gold at 67% premium ; how much gold was received ? Ans. $800. 176. Goods sold at 10% gain for $3300; what would have been the gain per cent if sold for $3600 ? Ans. 20%177. At what rate must I buy 7% bonds, in order to realize 10% on the investment? Ans. 70%178. In a sale of damaged goods for $1200, the loss was $300 ; what was the rate per cent? Ans. 20%. Yoyo. Bought a farm for $12000, on condition that 15% is to be paid in cash, 23% in 6 months, 17% in 12 months, 30% in 18 months, and the balance in two years; how much was the last payment? Ans. $1800. 180. Sold goods for $2500, which was $300 more than cost; what was the gain per cent ? Ans. 131% 7 181. What per cent of 35 is 3 ? Ans. 84%. 182. What per cent of 3 is 35 ? Ans. 11663%. 183. What is the amount of a 6% note for $1040, with interest from April 1st, 1875, to August 21st, 1878? Ans. $1251.463. a 184. BALTIMORE, MD., Jan. 1st, 1876. Three months after date, I promise to pay to John Smith or order, Five hundred dollars, for value received. JOHN JONES. What was due on this note April 16th, 1877? Ans. $531.25. 185. BALTIMORE, MD., Jan. 1st, 1876. Three months after date, I promise to pay Peter Post or order, One thousand dollars, for value received, with interest ; how much interest is due on this note July 21st, 1877 ? Ans. $933. -186. What is the value of a note for $1200, due 2 yr. 6 mo. previous to this date, at 6%, simple interest ? Compound interest payable annually and also semi-annually? Ans. At simple interest, $1380; compound interest, annually, $1388.77; compound interest, semi-annually, $1391.13. 187. Date of note April 1st, 1872, for $1000, at 6%, payments July 16th, 1873, $200; April 1st, 1875, $300; April 16th, 1876, $400. What is due July 1st, 1877 ? Ans. $331.57. 188. A note for $1000, dated April 1st, 1872, due in 3 years, with interest at 6%, payable annually, is endorsed as follows: Oct. 1st, 1873, $300 ; Jan. 1st, 1874, $200; what is due April 1st, 1875? Ans. $648.296. 189. A note for $500, dated April 1st, 1875, due 3 years, with interest at 6%, payable annually, is endorsed : April 1st, 1876, $130 ; Oct. 1st, 1876, $100; Oct. 16th, 1877, $100. Jan. 1st, 1878, the note is discounted in bank, without grace, at 8%; what sum is received from the bank ? Ans. $232.76. NOTE.—In the last two examples, as the interest is only due at the end of the year, the payments made during the year should bear interest until the settlement at the end of the year, and this method is called the Merchants' Rule, which is decidedly the most just method. 190. What is the difference of the amounts of $2000 at 6% for 12 years at simple, and at compound interest? Ans. $584.394. 7.191. What is the amount of $2000 at 6% simple interest for 20 years, also at compound interest ? Ans. Amount at simple interest, $4400; at compound interest, $6414.272. t 192. What is the compound amount of $1000 for 20 years 3 months ? Ans. $3255.243. NOTE.—When there are months or days, in compound interest, take from the table for the years and on this compound for the months or days, as you would from the table ; for 6 months multiply 1.03, when at 6%, and accordingly other times and rates. |