3. At what rate per cent will 742 dolls. 75 cts. in 5 years, amount to 965 dolls. 57 cts. 5 m. ? Ans. 6 per cent. 4. Suppose 837 dollars, at interest 4 years, amount to 1029 dofis. 51 cts. what was the rate per Ans. 53 per ct. cent? CASE 7. To find the time, when the principal, amount, and rate per cent. are given. As the interest of the principal for one year, Is to one year; So is the whole interest, To the time required. Note. If the interest for one year be found decimally, the above rule will so apply. EXAMPLES. 1. In what time will 5007. amount to 7251. at 5 per cent. per annum ? £. Year. £. As 25.. 1 :: 225 9 years, Answer. 2. In what time will 600 dells. amount to 856 dolls. 50 cts. at 4 per cent. per annum? Ans. 9y. 6. 3. A testator left his son, besides providing for his education, &c. 750l. to receive the amount thereof at 5 per cent. when he should arrive at the age of 21 years, which his guardian then found to be 1096l. 17s. 6d. how old was the boy at his father's decease? Ans. 11 years, 9 mo. 4. In what time will 742 dolls. 75 cts. amount to 965 dolls. Ans. 5 years. 57 cts. 5m. at 6 per cent. per annum ? 5. In what time will 837 dolls. amount to 1029 dolls. 51 cts. at 53 per cent. per annum? Ans. 4 years. 6. Suppose 312 dolls. at 6 per cent. per annum, amount to $77 dolls. 52 cts. how long was it at nterest? Ans. 3 years. I 2 A TABLE Of Days for any given time less than a Year. 1 132 60 2 233 61 3 3 34 62 4 435 63 5 6 91 121 152 182 213 244 274 305 335 92 122 153 183 214 245 275 306 336 93123 154 184 215 246 276 307 337 94124 155 185 216 247 277 308 338 53664 95 125 156 186 217 248 278 309 339 63765 96126157 187 218 249 279 310 340 7 73866 97 127 158 188219250 280 311 341 8 839 67 98 128 159 189 220 251 281 312 342 9 94068 99 129 160 190 221 252 282 313 343 10 10 41 69 100 130 161 191 222 253 283 314 344 11 11 42 70 101 131 162 192 223 254 284 315 345 12 12 43 71 102132163|193 224 255 285 316 346| 13 13 44 72 103 133 164 194 225 256 286 317 347 14 14 45 73 104 134 165 195 226 257 287 318 348 15 15 46 74 105|135|166|196227 258 288 319 349 16 16 47 75 106 136 167 197 228 259 289 320 350 17 17 48 76 107 137 168 198 229 260 290 321 351 |18|18|49|77|108 138 169 199 230 261 291 322 352 19 19 5078 109 139 170 200 231 262 292 323 353 2020 5179110140171201 232 263 293 324 354 21 2152 80 111 141 172 202|233|264|294|325 355 |22|22|53|81|112 142 173 203 234 265 295 326 356 23 23 54 82 113 143 174 204 235 266 296 327 357 24 24 55 83 114144175|205|236|267|297 328 358 25 25 56 84 115 145 176 206 237 268 298 329 359 26 2657 85 116 146 177 207 238 269 299 330 360 27 27 58 86 117 147 178 208|239|270 300 331 361 28 28 59 87 118 148 179 209 240 271 301 332 362 88 119 149 180 210 241 272 302 333 363 |89|120|150|181|211|242|273|303|334 364 212 243 29 29 30 30 31 31 190 151 304 365 THE USE OF THE TABLE. First, To know the number of days, from the beginning of the year, to any given day of any month; This is obtained by inspection only. Secondly, To find the number of days from any day in any Thirdly, To find the number of days between different dates: Suppose the 9th of the fifth month, and the 5th of the 11th month. From the number answering to 5th 11 mo. 309 129 Remains Days 180 Fourthly, To find the number of days from a given date, to some other in the year following: Suppose from 12th 10th mo. to 10th 6mo. ensuing. From 365 Take the number answering to 12th 10th mo. 285 To which add to the 10th 6 mo. Days required 80 161 241 Note. If the intercalary day of a leap-year intervene, one day must be added to those found as before. COMPOUND INTEREST. COMPOUND Interest, is that which arises from a principal, increased by its interest, as the interest becomes due. The ratio for Compound Interest, is the amount of one pound or dollar, for one year, at the given rate. IT IS THUS FOUND. L. or dol. L. or dol. L. or dol. L. or dol. Or, by adding the rate per cent. to 100%. or dollars, and moving the decimal point of the sum two places toward the left hand. CASE 1. When the time is any number of years; RULE -THE COMMON WAY. Find the first year's amount by simple interest, which will be the principal for the second year; and the amount of this, will be the principal for the third year, &c. From the last amount, take the given principal, and the re mainder will be the Compound Interest. RULE DECIMALLY. Multiply the principal by the ratio, and that product again by the ratio, &c. as often as there are years in the time: the last product will be the amount for the last year-From which take the given principal, and the remainder will be the Compound Interest. Note. The other cases will be in the latter part of the Book.. |