4. Three men, A, B, and C, trade in company, A puts in a certain sum, B puts in 3 times as much, and C puts in as much as A and B both; they gain $656. What is each man's share of the gain?

Ans. A's share $82; B's $246; C's $328.

5. A gentleman, meeting 4 poor persons, distributed 60 cents among them, giving the second twice, the third three times, and the fourth four times as much as the first. How many cents did he give to each ?

Ans. The first 6, the second 12, the third 18, and the fourth 24 cents.

6. A gentleman left 11000 crowns to be divided between his widow, two sons, and three daughters. He intended that the widow should receive twice the share of a son, and that each son should receive twice the share of a daughter. Required the share of each.

Let a represent the share of a daughter, then 2 x will represent the share of a son, &c.

Ans. The share of the widow was 4000 crowns; that of a son 2000, and that of a daughter 1000.

7. Four gentlen en entered into a speculation, for which they subscribed $4755, of which B paid 3 times as much as A, and C paid as much as A and B, and D paid as much as B and C. What did each pay?

Ans. A paid $317; B $951; C $1268; D $2219. 8. A man bought some oxen, some cows, and some sheep for $1400; there were an equal number of each sort. For the oxen he gave $42 apiece, for the cows $20, and for the sheep $8 apiece. How many were there of each sort?

In this example the unknown quantity is the number of each sort, but the number of each sort being the same, one character will express it.

Let a denote the number of each sort.

Then x oxen, at $42 apiece, will come to 42 x dolls., and a cows, at $20 apiece, will come to $20 x dolls., and x sheep, at $8 apiece, will come to 8 x dolls. These added together must make the whole price.

9. A man sold some calves and some sheep for $374, the calves at $5, and the sheep at $7 apiece; there were three times as many calves as sheep. How many were there of each?

Let x denote the number of sheep; then 3 x will denote the number of calves.

Then sheep, at $7 apiece, will come to 7 x dolls., and 3 x calves, at $5 apiece, will come to 5 times 3 x dolls., that is, 15 x dolls.

These added together must make the whole price.

The learner must have remarked by this time, that when a question is proposed, the first thing to be done, is to find, by means of the unknown quantity, an ex

pression which shall be equal to a given quantity, and then from that, by arithmetical operations, to deduce the value of the unknown quantity.

This expression of equality between two quantities, is called an equation. In the last example, 7 x + 15 x = 374 is an equation.

The quantity or quantities on the left of the sign = are called the first member, those on the right, the second member of the equation. (7x+15x) is the first member of the above equation, and 374 is the second member. Qantities connected by the signs and are called 7x and 15 x are terms in the above equation. The figure written before a letter showing how many times the letter is to be taken, is called the coefficient of that letter. In the quantities 7x, 15 x, 22 x ; 7, 15, 22, are coefficients of x.

terms.

The process of forming an equation by the conditions of a question, is called putting the question into an equation.

The process by which the value of the unknown quantity is found, after the question is put into an equation, is called solving the equation.

No rules can be given for putting questions into equations; this must be learned by practice; but rules may be found for solving most of the equations that ever

Occur.

After the preceding questions were put into equation, the first thing was to reduce all the terms containing the unknown quantity to one term, which was done by add

ing the coefficients.

As 7x+15x are 22 x. Then,

1

since 22 374, 1x must be equal to of 374. That is,

When the unknown quantity in one member is reduced to one term, and stands equal to a known quantity in the other, its value is found by dividing the known quantity by its coefficient.

10. A man bought some oranges, some lemons, and some pears, for 156 cents; the oranges at 6 cents each, the lemons at 4 cents, and the pears at 3 cents; there was an equal number of each sort. Required the number of each. Ans. 12 of each sort.

11. In fencing the side of a field, the length of which was 450 yards, two workmen were employed; one fenced 9 yards, and the other 6 yards per day. How many days did they work? Ans. 30 days.

12. Three men built 780 rods of fence; the first built 9 rods per day, the second 7, and the third 5; the second worked three times as many days as the first, and the third, twice as many days as the second. How many days did each work?

Ans. The first 13 days, the second 39, and third 78. 13. A man bought some oxen, some cows, and some calves for $348; the oxen at $38 each, the cows at $18, and the calves at $4. There were three times as many cows as oxen, and twice as many calves as cows. How many were there of each sort?

Ans. 3 oxen, 9 cows, and 18 calves. 14. A merchant bought a quantity of flour for $132; for one half of it he gave $5 per barrel, and for the

other half $7. whole ?

How many barrels were there in the

Let x denote one half the number of barrels.

Ans. 22 barrels.

15. From two towns, which are 187 miles apart, two travellers set out at the same time with an intention of meeting; one of them travels at the rate of 8, the other of 9 miles each day. In how many days will they meet? Ans. 11 days.

II. 1. A cask of wine was sold for $45, which was only of what it cost. Required the cost.

Let x denote the cost.

Three fourths of x may be written or 3. The

latter is preferable.

4

or 15, and x will be 4 times 15, or 60.

3 x

x = 60.

Observe, that is the same as of 3 x. Now if

: 4

of 3x is 45, 3 x itself must be 4 times 45, or 180; 3 x being 180, a must be of 180, which is 60.