8. If land m are the segments of a line, a, divided in extreme and mean ratio, and l>m,

a : l =l: m.

Art. 370.

10. In circles, C: C'R: R'; also C: C' = D ; D',

Art. 442.

2. In a triangle, Kys (sa) (s—b) (s—c).

Art. 393.

Ex. 4, p. 257,

Art. 385.

Art. 394.

9. In a segment of a circle, K-sector A formed by the chord

12. In two circles, K: K' = R2 : R"2 = 1)2 : D2=C2 : 0";

Art. 449.

Art. 399.

Art. 314.

Art. 452.

also R : R' =D : D' = C ; C" = V/K : VK'. Art. 314.

3. In a frustum of a regular pyramid, S=}(P+p) L._Art. 643.

6. In a frustum of a cone of revolution, S=TML (R+r). Art. 727.

4. In a frustum of a pyramid, = } H ( B + b + √ Bb). Art. 656.

10. In a frustum of a cone, F} H ( B + b + √ Bb).

Art. 729.

15. In a spherical segment of one base, V=TH2 (R − } H).

Art. 837.

Art. 838.

Similar tables are used for the unit of weight, the gram; for the unit of capacity, the liter; for the unit of land measure, the are; and for the unit of wood measure, the stere.

A liter

A gram

TABLE FOR SQUARE MEASURE

100 sq. mm. = 1 sq. cm.

100 sq. cm. =1 sq. dm., etc.

TABLE FOR CUBIC MEASURE

1000 cu. mm. 1 cu. cm.

1000 cu. cm. 1 cu. dm., etc.

= 1 eu. dm.

weight of 1 cu. cm. of water at 39.2° Fahrenheit.