SUGGESTION.

Write 6.121, 8.471, and 9.061, or 6.125, 8.475, and 9.0625.

50. From the sum of 6.63 and .835 subtract .3331.

51. Add 2.7, 491, .371, 2.51, 36.094, and 25.

WRITTEN EXERCISES

167. 1. In a recent year the average load of freight per train was 140 tons in Great Britain and 2873 tons in the United States. How much more did a freight-train load in this country weigh?

2. Find the difference in height between a locomotive wheel 61 feet high and a freight-car wheel 23 feet high.

3. It took a steam locomotive 33 minutes and an electric locomotive 2 minutes to attain a speed of fifty miles per hour. In how much shorter time did the electric locomotive attain that speed?

4. The cost per mile of running a suburban train by steam was: coal, 141; water, 1; crew, 121; maintenance, 61; supplies, . The cost with electrical equipment was: electric power, 103; crew, 6; maintenance, 4; supplies, the saving per mile with electricity.

. Find

5. Find the cost of a coal miner's outfit, as follows: drilling machine for coal, $81; drilling machine for rock, $83; pick, $; shovel, $; drill, $13; needle, $4; scraper, 1; ax, $1; saw, $3.

6. The United States 12-inch naval gun weighs 533 tons, the German gun of the same bore, 48 tons. How much less does the German gun weigh than the American?

7. The equipment of an American soldier in war time weighs 55 pounds. If the British soldier carries 3 pounds less and the German soldier 3 pounds more than the American, what is the weight of each one's equipment?

8. Following is the amount of the principal animal food annually consumed per person in a certain town: 19 pounds butter, 34 lb. ready-cooked meat, 343 lb. fish, 1543 lb. beef, 25 lb. pork, 275 lb. fowl and game. Find the total amount.

MULTIPLICATION

168. Multiplication of integers by fractions.

1. 123 +3 +3 +3.

12=2+2+2 +2 +2 +2.

What is 1 of the 4 equal parts of 12, or of 12?

Find of 12.

Find of 12, then &

2. Find of 50;

of 12.

of 100. Compare the results.
of 50 compare with

How does 2 times
Tell two ways of finding

3. Find of 8 by finding

of 2 times 50?

of 50, or of multiplying 50 by z. of 2 times 8.

Find of 35 by finding of 2 times 35; also find 2 of 35 in a shorter way. 4. Find 3 of 11; of 21; of 7; † of 45.

169. Finding a fractional part of a number is called multiplying by a fraction.

In using a fraction as a multiplier, we multiply by the numerator and divide by the denominator.

We may perform these two operations in either order; but it is better to divide first when the multiplicand exactly contains the denominator.

29. If the average coal miner works of a month of 30 days, how many days during the month does he work?

30. A recipe for fudge calls for of a cake of chocolate. If a cake costs 204, find the cost of the chocolate called for by the recipe.

31. In target practice the battleship Indiana shot at a target 24 times. If of the shots hit, how many successful shots were fired?

32. A collection of mail that required just 6 hours for a postman to make with a horse and wagon was made in an automobile in the time. How long did the automobile take?

33. How many corks per day does a machine in Spain make from the bark of the cork tree, if it makes of a sack of 15,000 corks in that time?

42. If of a magazine of 312 pages consists of advertisements, how many pages are left for reading matter?

How many

43. Of the 4,475 million communications that passed through the British post offices one year, were letters. letters did the British post offices handle?

44. Railroad statistics one year showed that there were 225,000 passenger coaches in the world, as many locomotives, and 13 times as many freight cars. Find the number of each.

45. The United States in a recent year turned out 600,000 tons of tin plate. If the Welsh mills manufactured 124 times as much, find their output for the year,