« ΠροηγούμενηΣυνέχεια »
same time, and B 8 dollars for the same time. A must have , B and C , of 88 dollars."
The examples 127, 128, 129, 130, and 131, are double or compound fellowship
139. The interest of 50 dollars for 1 year and 6 months is 4 dollars and 50 cents, and for 1 month it is 25 cents. The interest of 7 dollars for 18 months (a dollar is } of a cent a month) is 63 cents. The whole amounts to 5 dollars and 38 cents.
140. The interest of 200 dollars for 14 years is 16 dollars. The interest of 67 dollars is 67 cents for every 2 months, for 16 months it will be 8 times 67 cents, which are 5 dollars and 36 cents. The whole interest is 21 dollars and 36 cents. · 143. The interest of 100 dollars for 2years, is 13 dollars and 50 cents. The interest of 100 dollars for 60 days would be 1 dollar, the interest for 20 days will be ţ of a dollar, or 33} cents. The interest of 1 dollar for 21 years is 134 cents ; for 10 dollars the interest would be 1 dollar and 35 cents, and for 30 dollars, 4 dollars and 5 cents. The interest of my dollars for 21 years is 7 times 131 cents or 941 cents. The interest of 37 dollars for 60 days would be 37 cents, and for 30 days of 37 cents, or 12 cents. The whole interest is 18 dollars and 95 cents.
146. They would both together do f of the work in 1 day, and it would take them of a day to do the other 1. Ans. if day.
147. would be done in 1 day, and it would take $ of a day to do the other Ans. 14 day.
149. They both together consume of a bushel in a week, but the woman alone consumes only of a bushel in a week. That is, they both together consume % in a week, but the woman alone only P; consequently, the man alone would consume it ; and a bushel would last him 3} weeks.
162. A and B can build of it in 1 day; A, B, and C, can build of it in 1 day; the difference between $ and is ; therefore C can build it of it in i day: and it would take him 134 days to build it alone.
164. Find how much they might eat in a day, in order to make it last 1 month, and then it will be easy to find how much they may eat in a day, to make it last 11 months.
167. The money is 7 parts of the whole, and the purse one part; consequently the money is ), and the purse $ of 16.
170. He gave one part for the apple, 2 parts for the orange, and 4 parts for the melon. These make y parts. The apple 3 cents, the orange 6 cents, and the melon 12 cepts.
175. If to a number half of itself be added, the sum is of that number; hence subtract 24 from 100, and the remainder is of the number of geese that he had.
180. This must be reduced to 6ths. i half is , and 4 is , and the number itself is . If therefore to the whole number its half and its third be added. the sum will be ¥; hence, 77 is y of the number.
181. 1 is 7; therefore if to a number and t of itself be added, the whole number will be t; but when 18 more is added to 7, the first number is doubled; that is, the number is t of the first number; therefore 18 is * of the number.
Colburn's First Lessons, or, Intellectual
The merits of this little work are so well known, and so highly appreciated in Boston and its vicinity, that any recommendation of it is unnecessary, except to those parents and teachers in the country, to whom it has not been introduced. To such it may be interesting and important to be informed, that the system of which this work gives the elementary principles, is founded on this simple maxim; that, children should be instructed in every science, just so fast as they can understand it. In conformity with this principle, the book commences with examples so simple, that they can be perfectly comprehended and performed mentally by children of four or five years of age; having performed these, the scholar will be enabled to answer the more difficult questions which follow. He will find, at every stage of his progress, that what he has already done has perfectly pre
pared him for what is at present required. This - will encourage him to proceed, and will afford?
him a satisfaction in his study, which can never be enjoyed while performing the merely mechanical operation of ciphering according to artificial rules.
This method entirely supersedes the necessity of any rules, and the book contains none. The scholar learns to reason correctly respecting all combinations of numbers; and if he reasons correctly, he must obtain the desired result. The scholar, who can be made to understand how a sum should be done, necds neither book nor instructer to dictate how it must be donė.
This admirable elementary Arithmetic introduces the scholar at once to that simple, practical system, which accords with the natural operations of the human mind. All that is learned in this way is precisely what will be found essential in transacting the ordinary business of life, and it prepares the way, in the best possible manner, foi the more abstruse investigations which belong to maturer age. Children of five or six years of age will be able to make considerable progress in the science of numbers by pursuing this simple method of studying it; and it will uniformly be found that this is one of the most useful and interesting sciences upon which their minds can be occupied By using this work children may be farther advanced at the age of nine or ten, than they can be at the age of fourteen or fifteen by the common method. 'I'hose who have used it, and are regard ed as competent judges, have uniformly decided that more can be learned from it in one year, than can be acquired in two years from any other treatise ever published in America. Those who re
gard economy in time and money, cannot fail of holding a work in high estimation which will afford these important advantages.
Colburn's First Lessons are accompanied with such instructions as to the proper mode of using them, as will relieve parents and teachers from any embarrassment. The sale of the work has been so extensive, ihat the publishers have oeen enabled so to reduce its price, that it is, a! once, the cheapest and the best Arithmetic in the country.
This work consists of two parts, in tne first of which the author has given a great variety of questions, arranged according to the method purued in the First Lessons; the second part consists of a few questions, with the solution of them, and such copious illustrations of the principles involved in the examples in the first part of the work, that the whole is rendered perfectly intelligible. The two parts are designed to be studied together. The answers to the questions in the first part are: given in a Key, which is published separately for the use of instructers. If the scholar find any sum difficult, he must turn to the principles and illustrations, given in the second part, and these will furnish all the assistance that is needed.
The design of this arrangement is to make the scholar understand his subject thoroughly, instead of performing his sums by rule.