INTEREST TEST OF SUCCESS 114, 115, 178-179 120-121, 126, 142-143, 148-149, 151 124 125 128, 208, 209, 226-227 129, 131 130, 132-133, 237-239 138, 228-231 150, 168, 181 152-153 154-155, 202 157 186-187 188-189, 192 190, 193-194 206 218-221 234-235 236 240-242 256 24, 48, 52, 61, 74, 76-77, 88-89, 103-105, 122-123, 135137, 139-140, 156, 158-161, 171, 183, 185, 198-199, 203– 205, 207, 211-213, 217, 232-233, 243-249, 252–256. xiii FACTS FOR PROBLEMS A brick is 8 in. × 4 in. x 2 in. A flatiron weighs 6 lb. A roll of wall paper is 24 ft. x 18 in. A cubic foot of water weighs 1000 oz.; of ice, 930 oz. Passenger trains move at the rate of 40 mi. per hour. Fast mail trains can make a mile a minute. The greatest speed of the trotting horse is a mile in two minutes. At sea level the weight of air upon 1 sq. in. of surface is 14.7 lb. The cost of life insurance in "old-line" companies per $1000 is: At 26 yr. of age, $21; at 38 yr., $30; at 50 yr., $48.50. Letters are 2 per oz. and each fraction of ounce. Newspapers and periodicals, when mailed by.publishers, cost 17 per lb. In the ordinary course of the mail they cost 17 per 4 oz. Printed matter, unsealed, costs 1 per oz. Merchandise costs 1¢ per oz. Telegrams cost 25 for 10 words, with 2 for each additional word, for distances within the local telegraph district; within the next "zone," 40 for 10 words; etc. A dog weighs 40 lb.; a man, 150 lb.; a horse, 1000 lb.; an elephant, 8000 lb.; a locomotive, 150,000 lb.; an ocean steamship, 20,000,000 lb. Sound is a radiating energy, causing waves that travel 1080 ft. per sec. in the air and 4700 ft. per sec. in the ocean. Light is also a radiating energy, whose waves travel 196,000 mi. per sec. through the ether. Sun time varies 1 hr. in 800 miles, latitude of New York City. |