PTER XV BE ROOT Problems.-The cube root of a ich when cubed or raised to the that number. For example: ause 23 or 2 X 2 X 2 is 8. Also because 33 or 3 × 3 × 3 is 27. oot is Thus we have mber may be considered as the s of which represents the number. 10 is 1000 and a cube 10 in. on a 0 cu. in. of one side of a cube equals the representing the volume of the ber of ways of finding the cube actual calculation, (2) by use of of logarithms which we will take e use of some computing device his book may be found a table s of numbers, and from this table à cube root may be found very s it is better to work out cube on a handbook or table. ube root of any number first find ere are in the root. This is done aber into groups of three figures mixed numbe same as the n root we are fi has three figur cube root of 19 two groups. ( one, two, or thr Example.-Fin First point off each. This gives The largest number w is 2. This is the first subtract the cube of 2 fr remainder bring down th Next we square the roo it by 300. See how many 1200 is our trial divisor a once, we then take 1 The proceed as before, and after we h we multiply the total or 136116 answer, 6, and the operation is is no remainder. If it is desired to find the cul posed of a whole number and a mal point and point off grou Then find the root as before. of a decimal the first group is .000'015'625. In this case th is a cipher. The cube root of follows: 506,095 9. 4,057,719,875 10. 3,996,969.003 The answers to th standing the method yourself, step by st given. Suppose it is desire coal bin to hold 100 breadth, and depth o of 1000 cu. ft. or 101 If it is desired to fi tain a certain volum 3.1416 6 or .5236, and Many other uses of well to have a clear cube root of any num number, a fraction or X 5= 25/ 1525 7625 d' FIG. 127. each equal to d ft. .785 X d = 50 cu. 3 50 V.785 Find "d. 14. How many ti bearings 4 in. in dia in. in diam.? The 15. What is the weight of a lead 11.4 times as heavy as water? (Wa 16. How much space is left betwee and the inside surface of a cubical touches? 17. A test is made to find the diam ing the amount of water they displac put in a cylindrical vessel 4 in. in d What is the diameter of the bearing al used will red is the least when the height and the base are equal. Therefore reFig. 127, if the base and height are to d ft. the volume equals d XdX = 50 cu. ft., or .785d3 = 50 and d= Find "d." many times heavier are 1000 steel ball n. in diam. than the same numbers The steel weighs .28 lb. per cu. in. a lead ball 4 in. in diam. if lead is (Water weighs 62.5 lb. per cu. ft.) between the surface of a 2-in. sphere cubical box which the sphere just ne diameter of ball bearings by finddisplace. When 100 of the balls are in. in diam. the water rises 4.17 in. bearings? Solids, as shown i polygons (plane figure are parallelograms ( sided plane figures w sides are equal and called "Prisms.” Figures (a) and prisms as the center perpendicular to the solids. Fig. (a) sho prism, since its base and Fig. (c) is a he hexagon. Figure 129 shows |