GENERAL PRINCIPLES OF PERCENTAGE. Percentage is a term applied to operations in which 100 is the basis of computation. The same word is also applied to the result obtained by taking hundredths of any number. Per cent. is contracted from the Latin per centum, meaning by the hundred; and any number of hundredths of a given number is called so many per cent. of it. The Rate per cent. is the number of hundredths taken. The Base is the number of which the per is taken. cent. The Amount is the base plus the percentage. The Difference is the base minus the percentage. The most common applications of percentage are to Interest, Bank Discount, and True Discount, each of which will be specially treated of. We give here the general principles upon which they all depend. Any two of the five terms being given, the others may be found according to the following formulæ : A very common application of percentage occurs in the marking of goods by the retailer, who calculates to make a certain percentage of profit according to the character of the goods dealt in. It is worth noting that one-tenth of the price per dozen is the price for each article at a profit of 20%. Thus, if a merchant buys shoes at $48 per dozen pairs, to find the price at which he must sell them to gain 20%, he has only to move the decimal point one place to the left, giving $4.80 per pair. Or oranges, bought at 50 cts. a dozen, must sell for 8-5 cts. each, to net 20%. This fact is convenient at trade sales or other auctions, where there is no time for labored calculation. This rule may be extended as follows: To mark single articles, bought by the dozen. Move the decimal point of the price per dozen one place to the left. Then : 1. For what must I retail shirts, bought at $24 a dozen, to gain 35%? $2.40+2.40 $2.70 Ans. 2. Bought Anderson's United States Readers at $12 per dozen. For what must I retail them to gain 50%? $1.2010-$1.50 Ans. 3. Bought Jackson's Celestial Hemispheres at $90 per dozen pairs, and sold them at a profit of 331%. What is their retail price? $9.00+20=$10.00 Ans. 4. Bought for Japanese schools 12 Stellar Tellurians, costing, at 42 Barclay St., New York, $1200, and $828 for transportation. For what must they be sold at Yeddo, to clear 20% on the whole transaction? $120+$82.80 $202.80 Ans. 5. Bought hats at $17.00 per doz. and sold them for $1.70 each. What did I gain? 20% Ans. 6. A merchant buys gloves at $9.00 per dozen, and sells them for $1.05 per pair. What is his % of profit? 1050 corresponding in table to 40% Ans. 90 7. If Hammocks bought for $48 per dozen sell for $5.00 each, what is the % of profit? 500480 corresponding to 25% Ans. 8. For how much must I sell lead pencils bought at $3.00 per gross to make 44% ? $.025+25=$.03 each. Ans. Interest is money paid for the use of money. The money lent for use is called the Principal; the interest for a given time added to the principal, is called the Amount. The per cent. paid for the use of money one year, is called the Rate. The Present Worth of a sum of money due at a future time, is that amount which, put at interest now at the given rate, would then amount to that sum. True Discount is the difference between the present worth and the amount. Bank Discount is simple. interest collected in advance, three days, called Days of Grace, being added to the nominal time. 1 |