Beecham's help to scholars : containing arithmetical tables and signs, weights and measures, tables of the metric system, and other useful information / Thos. Beecham.

Beecham, Thomas

Date:: [1892?]

Credit: Beecham's help to scholars : containing arithmetical tables and signs, weights and measures, tables of the metric system, and other useful information / Thos. Beecham. Source: Wellcome Collection.

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$MENTAL ARITHMETIC AIDS—continued. To find a year’s income (Sundays included) at a given rate per day :— Take a sovereign, a half-sovereign, and five pence as many times as there are pennies in the given rate:—Example, 365 days at 17/5 per day. 17/5 = 209 pence (209 x £1 = £209) + (209 x 10/- = £104/10/-) + (209 x 5d. = !045d. - £4/7/1) £209 + £104/10/- + £4/7/i = £317/17/1 total. To find the cost of any number of articles when the price is an aliquot part of a sovereign :—Take the number as sovereigns and divide by the aliquot part. 2,786 at 3/4 each : 2,786 divided by 6 = £464. 6s. 8d. 1. To find the cost of a dozen:—Express cost of 1 in pence and fractions of a penny, and the answer is that number of shillings. 2. To find the cost of a score:—Express cost of 1 in shillings and fractions of a shilling, and the answer is that number of pounds. Simple Interest Formula.—Interest = P x R x T -f- 100. Principal = 1 x 100 -r R and T. Rate = I X 100 -r P and T. Time = Interest x 100 -f P and R. Mensuration Formula.—1.—Area of square, rectangle, rhombus or rhomboid = base x height. Base = area 4- height. Height = area 4- base. 2.—Area of Triangle = £ base x height. 3.—Area of Circle = d2 ,x *7854, or — r2 x 7r. 4.—Circumference = diameter x 7r. 5.—Cubical content of a box or volume of a solid = length x breadth x height. Length = volume 4- breadth, and height. Breadth = volume -r length and height. Height = volume 4- length and breadth. 6.—Vol. of Cylinder or Prism = base area x height. 7.— Vol. of Cone or Pyramid = ^ base area x height. 8.—Vol. of Sphere = |r3 x 7r. 9.—Surface of Sphere = 4r2 xtt or d2 x 7r. 10.—Area of Square = diagonal2-r 2. 11.—Side of Square = \ diagonal x V2. 12.—Diagonal of Square = side x V2. 13.—Area of any quadrilateral = diagonal x half sum of perpendiculars from opposite angles. 14.— Vol. of Log =» Length x (^ girth)2. Note.—t—3*1416 or 3\. Note—^2= 1*41421.$