| 100 | 100 | 100 | ||||
| 25 | 20 | 10 | ||||
| 75 | × | 80 | × | 90 | = | .540000 |
Subtract each from 100 and multiply and you get .54. $500 × .54 = $270, the agent’s price.
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Percentage.
The name percentage is applied to certain arithmetical exercises in which 100 is used as the basis of computation. Per cent. is an abbreviation of the Latin per centum, meaning by the hundred. This sign % is used for the words per cent. Thus, 10% of a number equals 10/100, or 1/10 of the number; 50% equals 50/100, or 1/2, etc.
FRACTIONAL EQUIVALENTS.
| 50 | % | = | .50 | = | 1/2. |
| 33 1/3 | % | = | .33 1/3 | = | 1/3. |
| 25 | % | = | .25 | = | 1/4. |
| 20 | % | = | .20 | = | 1/5. |
| 16 2/3 | % | = | .16 2/3 | = | 1/6. |
| 12 1/2 | % | = | .12 1/2 | = | 1/8. |
| 10 | % | = | .10 | = | 1/10. |
| 8 1/3 | % | = | .08 1/3 | = | 1/12. |
| 6 1/4 | % | = | .06 1/4 | = | 1/16. |
| 5 | % | = | .05 | = | 1/20. |
| 2 1/2 | % | = | .02 1/2 | = | 1/40. |
Accurate Interest.
Interest is the sum charged for the use of money. It is really the use of money or the benefit derived from its use. The principal is the sum for the use of which interest is paid. The rate of interest is the per cent. of the principal charged for its use for one year. Simple interest is the interest on the principal only, for the full time; compound interest is interest on the principal for the full time, and interest on each interest payment after it becomes due.