It is not easy to form an idea of what is meant by the term, Compound Number, and especially so, when we find it applied to such numbers as 3 pounds, 3 dollars, 3 shillings, &c. Why is 3 pounds a compound number any more than 3? If it be answered, that 3 pounds is composed or compounded of three single pounds, that does not remove the difficulty, for 3 is also composed of three units 1. Is it not then the better way to call the first a denominate number, and the other a simple number, as is done in § 45. Mr. Hasler, in his Arithmetic, has called this class of numbers, Denominate Fractions. In the present edition, the questions referring to each section are arranged directly after the section, which generally brings the question and answer on the same page. This alteration will, no doubt, be found convenient to teachers. A Key has also been prepared, in which all the questions contained in the Arithmetic are resolved, and in such a manner, that the particular methods of solution can be fully understood. Many examples, not in the Arithmetic, have been imbodied in the Key, in order that the pupils may be exercised in questions not found in the books before them. Hartford, Connecticut, March, 1838. MENTAL ARITHMETIC. PART I. 1. How many eyes have you? How many ears have you? How many hands have you? How many thumbs have you u? How many fingers have you on each hand? How many fingers have you on both hands? If you have one apple and Charles gives you one, how many will you have? One and one are how many? If you have one apple and Charles gives you two, how many will you have? One and two are how many? If he gives you three, how many will you have? One and three are how many? If he gives you four, how many will you have? One and four are? One and five are? One and six are? One and seven are? One and eight One and nine are? are? 2. If you have two nuts in one hand and one in the other, how many have you in both? Two and one are how many? If you have two nuts in one hand and two in the other, how many have you in both? Two and two are how many? If you have two nuts in one hand and three in the other, how many have you in both? Two and three are how many? If you have two nuts in one hand and four in the other, how many have you in both? Two and four are? Two and five are? Two and six are ? Two and seven are? Two and eight are? Two and nine are? 3. If you have three peaches in one basket and one in another, how many have you in both? Three and one are? If you have three in one basket and two in the other, how many? Three and two are? If you have three in one basket and three in the other, how many? Three and three are? Three and four are? Three and five are? Three and six are? Three and seven are? Three and eight are? Three and nine are? 4. If you have four oranges and buy one, how many will you have? Four and one are how many? If you buy two, how many will you have? Four and two are how many? If you buy three, how many will you have? Four and three are how many? Four and four are? Four and five are? Four and six are? Four and seven are ? Four and eight are? Four and nine are? Five 5. If you have five pears and mother gives you one, how many will you have? Five and one are how many? If she gives you two, how many will you have? and two are how many? If she gives you three, how many? Five and three are? Five and four are? Five and five are? Five and six are? Five and seven are? Five and eight are? Five and nine are? 6. If you have six marbles and James gives you one, how many will you have? Six and one are how many? If James gives you two, how many will you have? Six and two are how many? If he gives you three, how many will you have? Six and three are how many? Six and four are? Six and five are? Six and six are? and seven are? Six Six and eight are? Six and nine are? 7. If you have seven figs and buy one, how many will you have? Seven and one are how many? If you buy two, how many will you have? Seven and two are how many? If you buy three, how many will you have? Seven and three are how many? Seven, and four are? Seven and five are? Seven and six are? Seven and seven are? Seven and eight are? Seven and nine are? 1 8. If you have eight pencils and George gives you one, how many will you have? Eight and one are how many? If George gives you two, how many will you have? Eight and two are how many? If he gives you three, how many will you have? Eight and three are how many? Eight and four are? Eight and five are? Eight and six are? Eight and seven are? Eight and eight are? Eight and nine are? 9. If you have nine lemons and buy one, how many will you have? Nine and one are how many? If you |