PART 3d. COMPOUND ARITHMETIC,

IS that by which operations are performed with numbers whofe values are determined by the divifion and fubdivifion of the integer or unit, and is a compofition of the preceding RULES.

COMPOUND ADDITION,

IS the adding together of two or more compound numbers, to fhow their value in one fum.

RULE. Place all the given numbers of the fame denomination under each other; then, add the numbers of the first denomination together, and divide its fum by fo many as make one of the next denomination; fet the remainder under its column, and add the quotient to the next column; which add together and divide as before; thus proceed to the last denomination, under which, place its whole fum.

2 pf. 631 9

11

O pf.

the same situation it is now in (except the small loss of ") having no respect to the difference of time in which the sun enters the signs..

COMPOUND SUBTRACTION,

IS the fubtracting of one compound number from another, to find their difference.

RULE. Place each denomination of the lefs number, under the fame one of the greater; fubtract the first lower number from the firft upper one, and place the difference underneath; but if the lower number be the largeft, fubtract it from fo inany as make one of the next denomination; to this remainder add the upper number, which fum place underneath; then either add one to the lower number or take one from the upper, and proceed as before.

in

Motion.

Cc. S

will be in

- will be in

12 17 34 37 10+ fr Aries 1810 2 27 25 59

19+ from

S the Sun will

be fr. Aries

12 2 4 0 0 5 the Earth moves 11 20 8 37 51 This computation of time deviates from the Periodical Year 1,2564 d. If A be in latitude 75° 35′ 20′′ N. and in long. 7° 25′ 30′′ West from W. and B in 42 23 0 N. 4 20 32 West from W.

DESCENDING AND ASCENDING,

IS the changing of the form without altering the value. RULE 1. To reduce higher denominations to lower; multiply the highest denomination given by so many of the next as make one of the higheft; multiply this product by the next denomination, &c. and add to the product of each denomination the given parts of the fame name.

2. To reduce lower denominations to higher; divide the given denomination by fo many as make one of the next higher; divide this quotient by the next higher denomination, &c. if there by a remainder it is always of the fame name of the number divided

EXAMPLES.

In 6 £ 12 s 6 d. fterling, how many farthings?

6. 12 s. 6 d.

20 s in 1 £.

132 s. -12+120s. 12 d. in 1 fhilling.

1584 d.

6 d. given +

1590 x 46369 far. A.