A Key to the Standard Arithmetic and the Mental Arithmetic (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1901 Excerpt: ... x (31.416 + 25.1328) x 12 = 339.2928 sq. ft., lateral surface; 339.2928 sq. ft.-=-9 = 37.6992 sq. yd.; $.15 x 37.6992 = $5,654, the cost. 4. 9 ft. x 4 = 36 ft., perimeter of lower base; 8 ft. x 4 = 32 ft., perimeter of upper base; I x (36 + 32) x 10 = 340 sq. ft., lateral surface. The solution of the preceding example gives the area of the sides as 340 sq. ft. The area of the bottom is 9 x 9 or 81 sq. ft., 340 sq. ft. + 81 sq. ft. = 421 sq. ft., the area of the sides and bottom, which is the surface to be covered with sheet metal. 9.08 x 421 = $ 33.68, the cost. 1. 16" x 3.1416 = 706.86 sq. in., the surface; 706.86 + 144 = 4.908 sq. ft. 9. 13 Hl. = 1300 liters; 1300 liters = 1,300,000 cu. cm. Since a cubic centimeter weighs 1 gram, the whole weight will be 1,300,000 g.; 1,300,000 gr. + 1000 = 1300 Kg. 10. 1 cu. m. = 1,000,000 cu. cm., or 1,000,000 g.; 1,000,000 gr. = 1000 Kg. Since a liter has the volume of a cubic decimeter, or 1000 cubic centimeters, and since a gram of water has the bulk of a cubic centimeter, a liter of water must weigh 1000 grams. Hence 1,000,000 gr.--1000 gr. = 1000, the number of liters. 11. 65,750.75 1. = 65,750.75 cu. dm., or 65,750,750 cu. cm. or g.; 65,750,750 cu. cm. = 65.75075 cu. m.; 6,575,075 g. = 65,750.75 Kg. 18. 60 1. = 60 cu. dm., or 60,000 cu. cm. or g.; 60,000 g. = 60 Kg., the weight of water; 60 Kg. x 13.5 = 810 Kg., the weight of mercury. Page 415. 13.-1 cu. dm. = 1000 cu. cm. or g., the weight of water; 1000 g. x 7.21 = 7210 g., the weight of iron. 14. 1 eu. m. = 1.000,000 cu. cm. or g.; 1,000,000 g. = 1000 Kg.; 1000 Kg. x.92 = 920 Kg., the weight of ice. 15. 39.37079 in. H-36 in. = 1.0936, the number of yards in a meter; $2.90 x 1.0936 = $ 3.17, cost of a meter at $2.90 per yard. Therefore it is nf cheaper to ...