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Prealgebra 2e

Key Terms

Prealgebra 2eKey Terms

Key Terms

commission
A commission is a percentage of total sales as determined by the rate of commission.
discount
An amount of discount is a percent off the original price, determined by the discount rate.
mark-up
The mark-up is the amount added to the wholesale price, determined by the mark-up rate.
percent
A perfecnt is a ratio whose denominator is 100100.
percent decrease
The percent decrease is the percent the amount of decrease is of the original amount.
percent increase
The percent increase is the percent the amount of increase is of the original amount.
proportion
A proportion is an equation of the form ab=cdab=cd, where b≠0b≠0, d≠0d≠0.The proportion states two ratios or rates are equal. The proportion is read “aa is to bb, as cc is to dd”.
sales tax
The sales tax is a percent of the purchase price.
simple interest
If an amount of money, PP, the principal, is invested for a period of tt years at an annual interest rate rr, the amount of interest, II, earned is I=PrtI=Prt. Interest earned according to this formula is called simple interest.
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