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9. Find from the figures given below the world's total coffee production for a year :
10. Find from the figures given on page 9 the world's total production of petroleum for an average year:
PRODUCTION Bbl., 42 gal. 281,104,104 68,548,062 32,910,508 12,029,913 12,386,808 8,202,674 4,158,899 3,118,464 2,487,251
995,764 221,768 750,000 215,464 39,548 10,000
11. Find from the following figures the total United States
671,684 Other states
12. From the following figures, find the world's total railway
27,531 Australia, etc.
13. Find from the following figures the total number of libraries, and the total number of volumes in the libraries of the North Atlantic States :
Try the following examples by each of the methods given. Time yourself to see at what method you are most expert and accurate. Seek to perfect yourself in the use of that method.
To gain speed and accuracy in adding by groups requires constant practice. This develops a power which is of greatest service in most of the arithmetic the average person is called on to do.
13. Seven cars left Rutland, Vt., loaded with marble as follows: The first car, 36,675 pounds; the second, 36,850 ; the third, 37,200; the fourth, 37,650; the fifth, 37,150; the sixth, 38,090; and the seventh, 27,360. What was the total load ?
14. The enrollment in the common schools of certain states was found to be as follows: Illinois, 983,921; Ohio, 827,414; Missouri, 741,745; Iowa, 549,449; Indiana, 538,881 ; Michigan, 521,463; Wisconsin, 465,490; Minnesota, 429,012; Kansas, 381,595; Nebraska, 279,532; North Dakota, 124,000 ; South Dakota, 110,094. What was the total enrollment of all the states mentioned ?
15. The area of Virginia is 42,450 square miles; of Tennessee, 42,050 square miles; of Maryland, 12,210 square miles; of North Carolina, 10,200 square miles more than Tennessee ; and of Louisiana, 6270 square miles more than Virginia. What is the total area of these states ?
16. In one day a certain factory at Lowell turned out 17,200 buttons; in another, 18,560; in another, 18,570; in another, 16,500; and in another, 18,250. What was the total output for these five days?
Subtraction is the process of finding the difference between two numbers. The greater number is called the minuend and the smaller the subtrahend. The difference is sometimes called the remainder.
In performing the work it is customary, but not necessary, to write the number to be subtracted under the other number.
Check. - Add the remainder to the subtrahend. The result is the minuend.