Daboll's Schoolmaster's Assistant

EXAMPLES.

1. If an annuity of 70%. be forborne 5 years, what will be due for the principal and interest at the end of said term, simple interest being computed at 5 per cent. per annum ?

1st. Interest of 70l. at 5 per cent. for

Yr. £. s.

1-3 10

2d. And 5 yrs. annuity, at 70l. per yr. is

Ans. £385 0

2. A house being let upon a lease of 7 years, at 400£ dellers per annum, and the rent being in arrear for the whole term, I demand the sum due at the end of the term, simple interest being allowed at 67. per cent. per annum ? Ans. £3304.

To find the present worth of an annuity at simple interest.
RULE.

Find the present worth of each year by itself. discounting from the time it falls due, and the sum of all these present worths will be the present worth required.

EXAMPLES.

1. What is the present worth of 400 dols. per annum, to continue 4 years, at 6 per cent. per annum ?

377,35849 Pres. worth of 1st yr.

106

357,14285

118

124

338,98365
322,58064

2d yr

3d yr.

4th yr.

6 per cent, ?

Ans. $1396,06503=$1396, 6cts. 5m.

2. How much present money is equivalent to an annuity of 100 dollars, to continue 3 years; rebate being made at Ans. $268, 37cts 1m. 3. What is 807. yearly rent, to continue 5 years, worth in ready money, at 67, per cent. ? Ans. 6840 153, -f;

EQUATION OF PAYMENTS,

Is finding the equated time to pay at once, several debts

due at different periods of time, so that no loss shall be sus tained by either party.

RULE.

Multiply each payment by its time, and divide the sum of the several products by the whole debt, id the quotient will be the equated time for the paymes. of the whole.

EXAMPLES.

1. A owes B 380 dollars, to be paid as follows-viz. 100 dollars in 6 months, 120 dollars in 7 months, and 160 dollars in 10 months: What is the equated time for the pay ment of the whole debt ?

2. A merchant hath owing him 300l. to be paid as follows: 50%. at 2 months, 100%. at 5 months, and the rest at 8 months; and it is agreed to make one payment of the whole; I demand the equated time? Ans. 6 months.

3. Fowes H 1000 dollars, whereof 200 dollars is to be paid present, 400 dollars at 5 months, and the rest at 15 months, but they agree to make one payment of the whole; I demand when that time must be? Ans. 8 months. 4. A merchant has due to him a certain sum of money, to be paid one sixth at 2 months, one th ext 3 months, and the rest at 6 months; what is the equated time for the payment of the whole? Ans. 4 months

BARTER,

Is the exchanging of one commodity for another, and di

rects merchants and traders how to make the exchange withbut loss to either party

RULE.

Find the value of the commodity whose quantity is giv on; then find what quantity of the other at the pro

posed rate can be bought for the same money, and it gives the answer.

EXAMPLES.

1. What quantity of flax at 9 cts. per lb. must be give en in barter for 12 lb. of indigo, at 2 dois. 19 cts. per lb. ? 12 lb. of indigo at 2 dols. 19 cts. per lb. comes to 20 dol. 28 cts. therefore, As 9 cts. : 1 lb.:: 26,28 cts. : 292 the answer.

2. How much wheat at 1 dol. 25 cts. a bushel, must be given in barter for 50 bushels of rye, at 70 cts. a bushel? Ans. 28 bushels. 3. How much rice at 28s. per cwt. must be bartered før Scwt. of raisins, at 5d. per lb. ?

Ans. 5cwt 3qrs. 9}}†ē 4. How much tea at 4s. 9d. per lb. must be given in barter for 78 gallons of brandy, at 12s. 34d per gallon? Ans. 201lb. 13370z

5. A and B bartered: A had 81 cwt. of sugar at 12 cts. per lb. for which B gave him 18 cwt. of flour; what was the flour rated at per lb. ? Ans. 51cts.

6. B delivered 3 hhds. of brandy, at 6s. 8d. per gallon, to C, for 126 yds. of cloth, what was the cloth per yard? Ans. 10s. 7. D gives E 250 yards of drugget, at 30 cts. per yd. for 319 lbs. of pepper; what does the pepper stand him in per lb. Ans. 23cts. 51m. 8. A and B bartered: A had 41 cwt. of rice, ats. per cwt. for which B gave him 207. in money, and the rest in sugar at 8d. per lb.; I demand how much sugar B gave A besides the 207. ? Ans. Ecwt. Oqrs. 191b.

9. Two farmers bartered: A had 120 bushels of wheat at 11 dols. per bushel, for which B gave him 100 bushels of barley, worth 65 cts. per bushel, and the balance in oats at 40 cts. per bushel; what quantity of oats did A re, ceive from B? Ans. 287 bushels.

10. A hath linen cloth worth 20d an ell-ready money; but in barter he will have 2s. B hath broadcloth worth 14s. 6d. per yard ready money, at what price ought B to rate his broadcloth in Irarter, so as to be equivalent to A's bartering price? Ans. 178. ABAgro,

11. A and B barter: A hath 145 gallons of brandy at 1 dol. 20 cts. per gallon ready money, but in barter he will have 1 dol. 35 cts per gallon: B has linen at 58 cts. per yard ready money; how must B sell his linen per yard in proportion to A's bartering price, and how many yards are equal to A's brandy?

Ans. Barter price of B's linen is 65cts. 21m. and he must give A 300 yds. for his brandy.

12. A has 225 yds. of shalloon, at 2s. ready money, per yard, which he barters with B at 2s. 5d. per yard, taking indigo at 12s. 6d. per lb. which is worth but 10s. how much indigo will pay for the shalloon and who gets the

best bargain?

Ans. 431lb. at barter price will pay for the shalloon, and B has the advantage in barter

Value of A's cloth at cash price, is

Value of 43lb. of indigo, at 10s. per lb.

£22

10 21 15

B. gets the best bargain. by £0

LOSS AND GAIN,

Is a rule by which merchants and traders discover their

profit or loss in buying and selling their goods: it also instructs them how to rise or fall in the price of their goods, so as to gain or lose so much per cent. or otherwise.

Questions in this rule are answered by the Rule of Three.

EXAMPLES:

1. Bought a piece of cloth containing 85 yards, for 191 dols. 25 cts. and sold the same it 2 dols. 81 cts. per yard; what is the profit upon the whole piece?

Ans. $47, 60cts. 2. Bought 121 cwt. of rice, at 3 dols. 45 cts. a cwt. and sold it again at 4 cts. a pound; what was the whole gain? Ans. $12, 87cts. 5m. 3. Bought 11 cwt. of sugar, at f4d. per lb. but could not sell it again for any more than 21. 16s. per cwt.; did I gain or lose by my bargain? Ans. Lost, £2 11s. 4d. 4. Bought 44 b. of tea for 61. 12s. and sold it again for 8. 10s. 6d. ; what was the profit on each pound?

Ans. 101d

5. Bought a hhd. of molasses containing 119 gallons, at 52 cents per gallon; paid for carting the same 1 dollar 25 cents, and by accident 9 gallons leaked out; at what rate must I sell the remainder per gallon, to gain 13 dol lars in the whole? Ans. 69cts. 2m.

II. To know what is gained or lost per cent.

RULE.

First see what the gain or loss is by subtraction; then As the price it cost is to the gain or loss: so is 1007. or $100, to the gain or loss per cent.

EXAMPLES.

1. If I buy Irish linen at 2s. per yard, and sell it again at 2s. 8d. per yard; what do I gain per cent. or in laying out 100%. As: 2s. 8d. : : 100l.: £33 6s. 8d. Ans. 2. If I buy broadcloth at 3 dols. 44 cts. per yard, and sell it again at 4 dols. 30 cts. per yard: what do I gain per cent. or in laying out 100 dollars?

$cts.

Sold for, 4, 30