or TRUCK, is the exchanging of one commodity for another. The word comes from the Spanish baratar, to deceive or circumvent in bargain- ing, perhaps because those who deal this way usually endeavour to overreach one another.
To transact properly, the price of one of the com- modities and an equivalent quantity of the other, must be found either by practice or by the rule of three.
Quest. 1. How many pounds of cotton, at 9d. per lb. must be given in bartar for 13 C. 3 Q. 14 lb. of pepper, at 2l. 16s. per C.?
First, Find the price or value of the commodity whose quantity is given as follows:
<table> <tr> <th>C.</th> <th>Q.</th> <th>lb.</th> <th>L. s.</th> </tr> <tr> <td>13</td> <td>3</td> <td>14 at 2</td> <td>16</td> </tr> <tr> <td></td> <td></td> <td>26</td> <td></td> </tr> <tr> <td>2l.</td> <td>10</td> <td>8</td> <td></td> </tr> <tr> <td>16s.</td> <td>1</td> <td>8</td> <td></td> </tr> <tr> <td>2Q.</td> <td></td> <td>14</td> <td></td> </tr> <tr> <td>1Q.</td> <td></td> <td>7</td> <td></td> </tr> <tr> <td>14lb.</td> <td></td> <td></td> <td></td> </tr> <tr> <td colspan="4">L.38 17</td> </tr> </table>
Secondly, Find how much cotton, at 9d. per lb. 38l. 17s. will purchase as under:
<table> <tr> <th>d.</th> <th>lb.</th> <th>L. s.</th> </tr> <tr> <td>If 9 : 1 :</td> <td>38 17</td> <td></td> </tr> <tr> <td></td> <td>20</td> <td></td> </tr> <tr> <td></td> <td>777</td> <td></td> </tr> <tr> <td></td> <td>12</td> <td></td> </tr> <tr> <td></td> <td>9)9324(</td> <td></td> </tr> <tr> <td colspan="2">Ans. 1036lb.=9</td> <td>1</td> </tr> </table>
If the above question be wrought decimally, the opera- tion may stand as follows:
C. L. C. If 1 : 2.8 :: 13.875 2.8 111000 27750 __________ lb. C. Q. .037538.8500(1036=9 1 Ans. 37.5 ... 1350 1125 2250 2250
The value or price of the goods received and delivered in bartar being always equal, it is obvious that the product of the quantities received and delivered, multi- plied in their respective rates, will be equal.
Hence arises a rule which may be used with advan- tage in working several questions; namely, Multiply the given quantity and rate of the one commodity, and the product divided by the rate of the other commodity quotes the quantity fought; or divided by the quantity quotes the rate.
Quest. 2. How many yards of linen, at 4s. per yard, should I have in bartar for 120 yards of velvet, at 15s. 6d.?
Yds. Sixp. Sixp. Yds. 120× 31 = 3720, and 8)3720(459 Ans.