Section 6.

INTEREST.

1. What is the interest of $144 for one year at 7 per cent.?

2. What is the interest of $850 for 1 year 7 months 18 days at 7 per cent. ?

NOTE. When the interest required is for months and days at 7 per cent., the better way is to find the interest of the principal at 6 per cent. by rule, (pages 120 and 121.) and to this sum add of the interest. Hence the preceding question should be performed in the following manner.

3. What is the interest of $865.75 for 3 years 9 months

24 days at 7 per cent. ?

4. What is the interest of $960.18 for 1 year 2 months at 7 per cent.?

5. What is the interest of $1728.19 for 3 years 8 months 10 days at 7 per cent. ?

6. What is the interest of $17.90 for 8 months 4 days at 7 per cent. ?

7. What is the interest of $1165.50 for 5 years 3 months 9 days at 7 per cent. ?

8. What is the interest of $1237.90 for 1 year 7 months 3 days at 7 per cent. ?

9. What is the interest of $156.80 for 3 years and 3 days at 7 per cent.?

10. What is the interest of $579.75 for 1 year 2 months 2 days at 7 per cent. ?

11. What is the interest of $7671.09 for 2 years 8 months

12. What is the interest of $943.11 for 1 month 29 days at 7 per cent.?

13. What is the interest of $975.06 for 2 years 7 months 9 days at 81 per cent. ?

NOTE. See note, page 121.

14. What is the interest of $1371.15 for 3 years 6 months 10 days at 11 per cent.?

15. What is the interest of $871.75 for 1 year 11 months 9 days at 8 per cent.?

16. What is the amount of $976.25 for 3 years 1 month 11 days at 12 per cent.?

17. What is the amount of $1000 for 3 years 3 months 29 days at 51 per cent. ?

18. What is the interest of $765 for two years 9 months at 1 per cent.?

19. What is the interest of $979.15 for 3 years 2 months 4 days at 21 per cent. ?

20. What is the interest of $760.75 from June 7, 1841, to March 9, 1843, at 7 per cent.?

NOTE. See rule, page 122.

21. What is the amount of $175.08 from May 7, 1841, to September 25, 1843, at 7 per cent. ?

22. What is the amount of $160 from December 11, 1843, to September 9, 1844, at 7 per cent. ?

23. What is the interest of $857.16 from February 26, 1841, to July 4, 1843, at 71 per cent. ?

24. What is the interest of $171.18 from March 15, 1842, to July 17, 1844, at 9 per cent. ?

25. What is the interest of $97.19 from August 17, 1843,

to November 9, 1844, at 7 per cent. ?

26. What is the amount of $765.75 from December 19, 1840, to October 11, 1843, at 6 per cent.?

27. What is the amount of $850 from March 19, 1843, to December 11, 1845, at 91 per cent.?

28. What is the amount of $769.87 from April 2, 1841, to January 19, 1843, at 7 per cent. ?

29. What is the interest of $1728.28 from June 7, 1842, to July 4, 1844, at 8 per cent.?

30. What is the amount of $ 565.25 from February 17, 1843, to January 1, 1845, at 8 per cent. ?

31. $960.

Newark, N. J., Oct. 23, 1840. On demand, I promise to pay S. S. St. John, or order, nine hundred sixty dollars, for value received, with interest at seven per cent. John Q. Smith.

Attest, H. F. Wilcox.

On this note are the following indorsements.

Sept. 25, 1841. Received one hundred forty dollars.

Two months after date, I promise to pay S. Durand, or order, one thousand dollars, for value received, with in

Oct. 9, 1843.

Received three hundred dollars.

What is due Dec. 1, 1844?

END

GREENLEAF'S SERIES OF ARITHMETICS.

MENTAL ARITHMETIC, upon the Inductive Plan; for Beginners.

INTRODUCTION TO THE NATIONAL ARITHMETIC, on the Inductive System; combining the Analytic and Synthetic Methods, with the Cancelling System; in which the principles of Arithmetic are explained and illustrated in a familiar manner. Designed for Common Schools. 196 pages, 12mo.

THE NATIONAL ARITHMETIC, on the Inductive System; combining the Analytic and Synthetic Methods, in which the principles of Arithmetic are explained in a perspicuous and familiar manner; containing also practical Systems of Mensuration, Gauging, Geometry, and Book-keeping; with an Appendix, comprising the CANCEL LING METHOD; forming a complete Mercantile Arithmetic. Designed for Common Schools and Academies. By BENJAMIN GREENLEAF, A. M., Principal of Bradford Teachers' Seminary. 324 pages, 12mo.

COMPLETE KEYS TO THE INTRODUCTION AND NATIONAL ARITHMETICS, containing full solutions and explanations, are published, for the convenience of teachers only, in two volumes.

The above books are handsomely printed and durably bound, and are sold at reasonable prices.

The attention of Teachers and Superintendents of Schools generally is re spectfully invited to this popular system of Arithmetic, which is well adapted to all classes of students. The "National Arithmetic" has been extensively introduced in various sections of the United States, and is highly recommended by many distinguish ed teachers who have used it, for its adaptedness to give pupils a thorough practical knowledge of the science. To those who have not had an opportunity to examine the work, the following testimonials are submitted.

Phillips Academy, (Teachers' Seminary,) Andover, Mass., Feb. 10, 1844. B. Greenleaf, Esq.- We have adopted the "National Arithmetic" as a text-book in this Institution. Having examined most of our popular systems of Arithmetic, I can say with sincerity, that I regard your book as better adapted to meet the wants of Academies, and the higher classes in Common Schools, than any other treatise on the subject. (Signed) W. H. WELLS, Instructer in English Department. From the late Principal of the Young Ladies' High School, Boston, Author of "First Lessons in Algebra," and other popular School Books.

I have examined with great care Mr. Greenleaf's "National Arithmetic," and have used it as a text-book for my pupils. In my view, the plan and execution of the work are quite perfect, the rules being deduced analytically from examples, and followed by copious questions for practice. The pupil can hardly fail to understand as he ad vances; nor can he go through the book without being a master of the science of Arithmetic. This is not an old book with a new name, but the work of one who thor oughly understands the subject, and who has learned, from a long and successful experience in teaching, how to prepare one of the very best school books which has ever been issued from the American press.

Very respectfully,

E. BAILEY.

From H. Morrison, Esq., Professor of Mathematics and President of the Universi ty of Maryland, Baltimore.

Greenleaf's Arithmetic is one of the most complete books of its kind, both in the extent and arrangement of its matter, that has yet appeared. Combining, as it does, the Analytic and Synthetic Methods, and abounding in familiar examples, it is admirably calculated to interest the pupil, and lead him, by easy and progressive steps, through the difficulties of the science, to its complete mastery, and full comprehension. To make the work more perfect than a treatise on Arithmetic merely could be, the author has added many geometrical, mechanical, philosophical, and astronomical problems, and a concise system of book-keeping, so that without the aid of any other book, , it i is calculated to make the perfect business man, in all his various departments. H. MORRISON.

Greenleaf's Arithmetic is the text-book in the Normal Schools in Massachusetts and New York city; and the best schools of Boston, New York, Philadelphia, Charleston, and other cities.

Published by ROBERT S. DAVIS, School-Book Publisher, BOSTON, and sold by the principal Booksellers throughout the Union.