5. $144 gain $128.52 in 12 yr. 9 mo.?
6. $220 gain $82.36 in 3 yr. 8 mo.?

7. $420 gain $42.30 in 2 yr. 9 mo. 24 da.?
8. $9.10 gain $5.115 in 9 yr. 9 mo. 9 da.?

9. $100 double itself in 3 yr.? 5 yr.? 6 yr.? 10. Any principal treble itself in 7 yr.? 8 yr.? 20 yr.?

3. Find the time in which:

1. $500 will produce $60 interest at 6%.
2. $1200 will produce $48 interest at 8%.
3. $230 will produce $27.60 interest at 6%.
4. $25.20 will produce $8.30 interest at 7%.
5. $70.50 will produce $26.50 interest at 7%.
6. $50 will produce $50 interest at 6%.

7. $300 will double itself at 8%.

8. $200 will double itself at 5%.

6%. 7%.

9. Any principal will double itself at 41%. 10. Any principal will treble itself at 6%. 7%. 8%.

PROBLEMS.

1. Find the exact interest of $680.20, at 71%, for 73 days. 2. What sum, bearing interest at 44%, will yield an annual income of $1500?

3. Find the amount of $1040 for 2 mo. 3 da., at 6%.

4. How long must $1952.46 be on interest, at 6%, to amount to $2284.38?

5. At what rate per cent. will $6000 produce $500 interest in 1 yr. 10 mo. 7 da. ?

COMPOUND INTEREST.

Compound Interest is interest computed, at certain intervals, on both the principal and unpaid interest. Such intervals are commonly 1 yr., 6 mo., or 3 mo.

MODEL SOLUTIONS.

1. Find the amount of $70, at compound interest for 3 yr.. at 6%; also the compound interest.

Int. for 3d yr. =

74.20 .06 $4.45. Amt.

78.65 .06 = $4.72. Amt. = $83.37. X (Amt.) $83.37-(Pr.) $70.00 $13.27, compound interest. Hence the formula:

=

$78.65.

2. Find the compound interest of $630 for 2 yr. 6 mo.,

1. Find the compound interest of $200, at 7%, for 3 yr.

6 mo.

2. What is the amount of $458.50 for 2 yr., interest compounded semi-annually, at 6% ?

Suggestion: Compute for four intervals at 3%.

3. Compute the compound interest of $580 for 1 yr. 3mo., interest compounded quarterly, at 8%.

Five intervals, 2%.

4. Find the compound interest, at 6%, on $2000 for 1 yr. 10 mo., interest payable semi-annually.

5. What is the compound interest of $525.75 for 3 yr. 4 mo., at 6%?

6. Find the compound interest on $1050 for 1 yr. 6 mo., at 5%, interest being compounded quarterly.

7. Compute the compound interest of $600 for 2 yr. 3 mo., at 4%, interest being compounded semi-annually.

8. Find the compound interest of $20,000 for 6 mo., at 6%, interest being compounded monthly.

ANNUAL INTEREST.

Annual Interest is interest on the principal and each year's interest from the time each interest is due until settleAnnual interest is computed when the words "with interest payable annually" are in the contract.

ment.

MODEL SOLUTION.

Find the interest of $300 for 3 yr. 6 mo. 20 days at 4%, payable annually.

Int. for each of the 3 yr. = $12.00. The $12 will be on

interest:

Hence the following brief directions:

1. Find int. of Pr. for whole time.

2. Find int. of Pr. for one yr.

3. Find the sum of the time intervals.

4. Find int. on the one year's int., for the sum of the time intervals.

5. Find the sum of int. first found and int. last found.

EXERCISES.

1. Find the annual interest of:

1. $360 for 4 yr. 5 mo. 16 da. at 6%.
2. $250 for 3 yr. 9 mo. 12 da. at 7%.
3. $3500 for 4 yr. 6 mo. at 6%.

4. $1247.75 for 3 yr. 5 mo. 10 da. at 6%.
5. $987.25 for 4 yr. 9 mo. 6 da. at 4%.
6. $1098.36 for 5 yr. 10 mo. 7 da., at 5%.
2. Find the amount, at annual interest, of:
1. $360 for 4 yr. 5 mo. 16 da. at 5%.
2. $250 for 3 yr. 9 mo. 12 da. at 7%.
3. $600 for 3 yr. 4 mo. 12 da. at 6%.
4. $840 for 4 yr. 8 mo. 18 da. at 51%.

5. $2180 for 6 yr. 11 mo. 27 da., at 41%.

6. $1070 for 5 yr. 10 mo. 24 da. at 4%, the interest of the first two years having been paid.

PROMISSORY NOTES.

1. A Promissory Note is a promise, made in writing, to pay a sum of money on demand or at a specified time.

2. The Face of a note is the sum of money named in it. 3. The Maker of a note signs it. The Payee receives payment for it. The Holder has rightful possession of it.

4. The Endorser of a note writes his name on the back of it, and thus becomes responsible for payment of it.

5. A Negotiable Note is one that is transferable.

6. Notes are said to be negotiable or transferable when they contain the words "or bearer," or "or order," but no transfer of the latter can be made without the endorsement of

the payee.

To insure the negotiability of a note, in Pennsylvania the words" without defalcation" should be added. In New Jersey the words "without defalcation or discount" should be added; in Missouri, "negotiable and payable without defalcation or discount."

7. The words "with interest" render the note interestbearing from its date.

8. A note not containing the words "with interest" begins to bear interest at maturity if not paid.

9. The words "value received" are proof that the note represents actual value.

10. The day of maturity of a note is the day when it becomes due.

11. In any case, when the rate per cent. is not specified the legal rate is always understood.

12. Interest computed at a higher rate than the law allows is called usury.

13. In many States the time of payment is postponed three days, called "Days of Grace."

14. A Protest is a notice sent to the endorsers that the maker of the note has failed to pay it. The protest, to be valid, must not be sent later than the last day of grace.

15. A note signed by two or more persons, who thus become jointly and severally responsible for its payment, is called a Joint or Several Note.