Beecham's help to scholars : containing map of the world, essential dates of British History, arithmetical tables and signs, geographical & geometrical definitions, foreign words and phrases, and other useful information arranged progressively / Beechams Pills Ltd.

Beechams Pills Ltd.

Date:: 1938

Credit: Beecham's help to scholars : containing map of the world, essential dates of British History, arithmetical tables and signs, geographical & geometrical definitions, foreign words and phrases, and other useful information arranged progressively / Beechams Pills Ltd. Source: Wellcome Collection.

12/36 page 10

$MENTAL ARITHMETIC AIDS—continued. To find a year’s income (Sundays included) at a given rate per day :— Take a sovereign, a half-sovereign, and five pence as many times as there are pennies in the given rate :—Example, 365 days at 17/5 per day. 17/5 = 209 pence (209 x £1 = £209) + (209 x 10/- = £104/10/-) + (209 x 5d. = 1045d. = £4/7/1) £209 + £104/10/- + £4/7/1 = £317/17/1 total. To find the cost of any number of articles when the price is an aliquot | part of a sovereign :— Take the number as sovereigns and divide by the aliquot part. 2,786 at 3/4 each: 2,786 divided by 6 = £464. 6s. 8d. 1. To find the cost of a dozen :—Express cost of | in pence and fractions of a penny, and the answer is that number of shillings. 2. To find the cost of a score:—Express cost of | in shillings and fractions of a shilling, and the answer is that number of pounds. Simple Interest Formule.—Interest = P x R x T + 100. Principal = ]x 100+ Rand T. Rate=I x 100 + P and T. Time= Interest x 100 + P and R. Mensuration Formule.—|.—Area of square, rectangle, rhombus or rhomboid = base x height. Base = area + height. Height = area + base. 2.—Area of Triangle = $ base x height. 3.—Area of Circle = d? x ‘7854, or =r? x a. 4.—Circumference = diameter, x 7. 5.—Cubical content of a box or volume of a solid = length x breadth x height. Length = volume + breadth and height. Breadth = volume + length and height. Height = volume + length and breadth. 6.—Vol. of Cylinder or Prism = base area x height. 7.— Vol. of Cone or Pyramid = § base area x height. 8.—Vol. of Sphere = 4r3x a. 9.—Surface of Sphere = 4r? x r or d? xX. 10.—Area of Square = diagonal? + 2. 11.—Side of Square = } diagonal x V2. 12.—Diagonal of Square = side x V2. 13.—Area of any quadrilateral -- diagonal x half sum of perpendiculars from opposite angles. 14.— Vol. of Log = Length x (% girth)?. Note.—1=3'1416 or 34. Note—v 2 = 1°4142],$