22. Write MDCLXVI in Arabic notation. MDCLXVI = M + DC + LX + VI A dash over a letter increases its value one thousand fold. Thus, X = 10,000; L = 50,000. 38. Write these letters so that they shall represent 1000 times their ordinary value: I V C D M 39. Where are Roman numerals used? Numbers may be expressed in three ways: (1) by words; (2) by figures; (3) by letters. 40. In each of these three ways express your age; the number of days in a week; the number of months in a year; the number of weeks in a year; the number of minutes in an hour; the number of hours in a day; this page of the book; this year; the year in which you were born. Addition is the process of uniting two or more numbers into one number. What is the sign of addition? What is it called? What does it show? What name is given to the result in addition? Add 2 to each number in the diagram. Add 1; 3; 4; 5; 6; 7; 8; 9. Find the sum of the numbers in the diagram. Beginning with 1; 2; 3; 4; 5; 6; 7; 8; 9, add the numbers in the diagram. To each number in the table add 2; 3; 4; 5; 6; 7; 87 +40 + 6; think 127, 133; say 133. 8; 9; 10; 11; 12. 80; 90. Add other numbers to the numbers in the table. Thus, 87 + 46; ADDING TWO COLUMNS AT ONCE Sight Find the sum, adding both columns at once: Thus in number 1: 11, 22, 31, 35, 45, 52, 64. Beginning with 1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12; 20; 21, add the numbers in examples 1 to 12. Why are units written under units, tens under tens, etc., in adding numbers? NOTE. Pupils should be required to prove work in fundamental processes until accuracy becomes a habit. 1. Find the total area of these possessions of the United States: Alaska, 590,844 square miles; Guam, 210 square miles; Hawaii, 6499 square miles; Panama Canal Zone, 474 square miles; Philippine Islands, 115,026 square miles; Porto Rico, 3435 square miles; and the Tutuila Group, 77 square miles. 2. In one month Mr. Blanchard paid $17.50 for rent, $14.87 for groceries, $12.68 for provisions, $2.94 for milk, $1.50 for ice, $3.75 for shoes, $7.55 for clothing, and $3.29 for other expenses. What was the total? TABLE OF ELECTRIC RAILWAYS IN THE UNITED STATES IN 1908 3. Find the total number of companies; miles of track used; cars operated. 4. There are in the United States 148 streams with a navigable length of 5305 miles flowing into the Atlantic, 54 with a navigable length of 7641 miles flowing into the Gulf, 53 with a navigable length of 11,483 miles flowing into the Mississippi, 2 with a navigable length of 315 miles flowing into Canadian waters, and 38 with a navigable length of 1606 miles flowing into the Pacific. Find the total number of navigable streams. The total number of miles navigable. |